MXPA99011581A - Targeted liposomal constructs for diagnostic and therapeutic uses - Google Patents

Abstract

This invention provides a liposomal construct for delivering a diagnostic or therapeutic agent to a mammal comprising a liposomal carrier, a diagnostic or therapeutic agent entrapped within or associated with said liposomal carrier and a sequestering agent distributed within said liposomal carrier to reduce leakage of the diagnostic or therapeutic agent from the liposomal construct prior to delivery.

Description

LIPOSOMAL CONSTRUCTS DIRECTED FOR THERAPEUTIC AND DIAGNOSTIC USES FIELD OF THE INVENTION This invention relates generally to liposomal constructs useful for the administration of biologically active diagnostic and therapeutic agents. It particularly relates to a high integrity liposomal construct containing a biogenic amine, pharmaceutical compositions thereof, and methods of treating disease states therewith. DESCRIPTION OF THE RELATED ART Various lipid formulations and methods for their preparation for the administration of pharmaceutically active agents to a host have been described. Geho and Lau in U.S. Patent No. 4,603,044 describe a liposomal delivery system directed to deliver a drug to the liver's hapatobiliary receptors. The system comprises a drug or diagnostic agent encapsulated in structures with a lipid membrane or associated with such structure in vesicle or liposome forms, and a molecule having a fatty substituent fixed on the vesicle wall and a substituent white which is a chemical agent attracted to bile, for example a complex of iminodiacetate substituted. The system is especially useful for supplying insulin and serotonin for the treatment of type I and II diabetes, respectively. In U.S. Patent No. 4,761,287, Geho describes the administration of serotonin to the liver using a hepatocyte-directed vesicle (HDV). It was shown not only that the HDV-serotonin construct could deliver effective amounts of serotonin to the hepatocytes, but also that the potency was substantially higher than expected. Geho and Lau in U.S. Patent No. 4,863,896 show that the administration of insulin in a vesicle directed toward hepatocytes together with a simultaneous supply of free insulin allows a highly significant reduction of the total daily dosage of insulin required to control glucose in the blood. The presentations of the aforementioned patents, as well as the presentation of all other patents and publications mentioned in this specification, are explicitly incorporated by reference herein. SUMMARY OF THE INVENTION It is an object of the present invention to provide a means for improving storage stability and administration efficiency of diagnostic and therapeutic agents, for example, biogenic amines, in liposomal formats. This invention therefore offers a liposomal construct for the administration of a diagnostic or therapeutic agent to a mammal, comprising a liposomal vehicle, a diagnostic or therapeutic agent entrapped within said liposomal vehicle or associated with said liposomal carrier, and a sequestering agent distributed within said liposomal vehicle in an amount effective to minimize leakage of the diagnostic or therapeutic agent from the liposomal construct prior to administration. Preferably, the liposomal construct has targeting portions associated with its surface to direct the construct to a desired site. Pharmaceutical compositions of the liposomal constructs are also provided with pharmaceutically acceptable excipients and methods for the treatment of mammalian conditions with the compositions. Especially preferred is the treatment of conditions that respond to biogenic amines, particularly the treatment of type II diabetes with serotonin or a serotonergic agonist. DESCRIPTION DETAIL OF THE INVENTION In a broader aspect, this invention provides a liposomal construct for administering a diagnostic or therapeutic agent to a mammal, comprising a liposomal vehicle, a diagnostic or therapeutic agent entrapped within said liposomal vehicle associated with said agent. Liposomal vehicle and a sequestering agent distributed within said liposomal vehicle in an amount effective to minimize leakage of the diagnostic or therapeutic agent from the liposomal construct prior to administration. The particular diagnosis or the therapeutic agent used does not impose significant limitations on the scope of the invention. It is considered that any agent susceptible to entrapment or liposomal association, and whose administration can benefit from said association, is useful, for example, antibiotics, antidepressants, anti-tumor agents, antivirals, cytokines, hormones, imaging agents, neurotransmitters, stimulants, and the like. In one embodiment, the diagnostic or therapeutic agent is a biogenic amine, which includes sympathomimetic amines, naturally occurring catecholamines, and mimetics and autacoids. Representative biogenic amines include, but are not limited to, L-beta-3,4-dihydroxyphenylalanine (L-DOPA), 3- (2-aminoethyl) -5-hydroxyindole (5-hydroxytryptamine or serotonin), 2- (4- imidazolyl) ethylamine (histamine), 4- [l-hydroxy-2- (methylamino) ethyl] -1,2-benzenediol (epinephrine), 1- [3,4-dihydroxyphenyl] -2-aminoethanol (norepinephrine), gamma acid -amino-n-butyric, acetylcholine, serotonergic agonists and an amino acid in a preferred embodiment, the biogenic amine is serotonin or a serotonergic agonist. As used herein, the terms "serotonin analog" and "serotonergic agonist" refer to compounds that mimic the activity of serotonin, particularly compounds that act on the 5-HT2A / 2C receptors of hepatocytes, said interaction being blocked by metilsergida . The invention is based on the discovery that the leakage of biogenic amines from a liposomal construct during storage or after in vivo administration to a warm-blooded host can be minimized by loading the liposomal core volume with nucleotide, phosphate and phosphatidylphosphate derivatives, or polymeric amino acid constructs, which trap and sequester the biogenic neurotransmitters within the targeted liposomal delivery system until release at the desired site. The leak does not have to be eliminated to obtain the object of this invention, but simply reduced to a tolerable amount that varies with the type of active agent, its final concentration, end conditions of use, and storage variables. After administration to the host, a leak is considered undesirable when an amount of trapped agent sufficient to induce a physiological response escapes from the construct before reaching the desired site. The liposomal construct contains a sequestering agent selected from nucleotide derivatives, polyphosphate derivatives, phosphatidylphosphate derivatives, and amino acid polymers. Generically, the sequestering agent comprises a non-diffusible anionic polymer. Nucleotide derivatives include, but are not limited to, adenosine 5"-triphosphate (ATP), cytidin 5 '-triphosphate (CTP), guanosine 5'-triphosphate (GTP), thiin 5' -triphosphate (TTP), uridine 5 '-triphosphate (UTP), adenosine 5'-diphosphate (ADP), cytidine 5'-diphosphate (CDP), guanosine 5'-diphosphate (GDP), thymidine 5'-diphosphate (TDP), uridin 5' -diphosphate (UDP) ), adenosine 5'-monophosphate (AMP), cytidin 5 '-monophosphate (CMP), guanosine 5'-monophosphate (GMP), thymidine 5'-monophosphate (TMP), uridin 5'-monophosphate (UMP), adenosine 5' -tetraphosphate, guanosine 5'-tetraphosphate and thymidine 5'-tetrahydrate The amino acid polymer can be, for example, a copolymer of aspartic acid and glutamic acid Polyphosphate derivatives include, but are not limited to, phytic acid and hexaphosphate. Inositol and phosvitin In one embodiment, a component of the liposomal carrier membrane is a phosphatidylphosphate derivative, such as, for example, phosphatidic acid, phosphatidyl diphosphate, trif phosphatidylium osphate and phosphatidylinositol 4,5-diphosphate. Optionally, the liposomal construct has a focusing portion associated with its surface to be fixed on a receptor associated with a focused site, such as a biliary attraction molecule. Bile attraction molecules can be substituted iminodiacetic acids, N 'substituted derivatives of ethylene diamine N, N-diacetic acid (EDDA), hepatobiliary dyes, hepatobiliary contrast agents, bile salts, hepatobiliary linden complexes, and hepatobiliary complexes (including hepatobiliary amine complexes). Specific examples include, but not limited to, iminodiacetic N- (2,6-diisopropilfenilcarbamoilmetil) iminodiacetic acid, N- (2,6-diethylphenyl carbamoylmethyl), N- (2,6-dimetilfenilcarbamoilmetil) iminodiacetic acid, N- (4-isopropilfenilcarbamoil-methyl) iminodiacetic acid, N- (4-butilfenilcarbamoilmetil) iminodiacetic acid, N- (2,3-dimetilfenilcarbamoilmetil) iminodiacetic, N- (3-butilfenilcarbamoilmetil) iminodiacetic acid, N- (2 -butilfenilcarbamoilmetil) iminodiacetic acid, N- (4-terciar-butilfenilcarbamoilmetil) iminodiacetic, N- (3-butoxifenilcarbamoil-methyl) iminodiacetic acid, N- (2-hexiloxifenilcarbamoilmetil) iminodiacetic acid, N- (4-hexiloxifenilcarbamoilmetil) iminodiacetic acid / iminodiacetic azo substituted iminodicarboximetil-2-naphthyl ketone, complexone phthalein, N- (5, pregnen-3-beta-ol-2-oilcarbamoilmetil) iminodiacetic 3a: the 7th: 12th: acid trihydroxy-24-norcholanil-23-iminodiacetic N- acid ( 3-bromo-2, 4, 6-trimetilfenilcarbamoilmetil) iminodiacetic acid etiliminodiacético benzimidazole, N- (3-cyano-4, 5-dimethyl-2, pirrilcarbamoilmetil) iminodiacetic, ethylenediamine-N, N-bis (-2-hydroxy -5-bromo-phenyl) acetate, N'-acyl and N'-sulfonyl ethylene diamine N, N diacetic; N'-acetyl EDDA, N'-benzoyl EDDA, N'- (p-toluenesulfonyl) EDDA, N '- (Pt-butylbenzoyl) EDDA, N' - (benzensulfonyl) EDDA, N "- (p-chlorobenzenesulfonyl) EDDA, N'- (p-ethylbenzenesulfonyl) EDDA, N'- (pn-propylbenzenesulfonyl) EDDA, N'- (naphthalene-2-sulfonyl) EDDA, N '- (2/5-dimethylbenzensulfonyl) EDDA, N- acid ( 2-acetylnaphthyl) iminodiacetic acid, N- (2-naphthyl) methyl) iminodiacetic acid, rose bengal, congo red, bromosulftalein, bromophenol blue, phenolphthalein, toluidine blue, indocyanine green, iodipamide, ioglycolamic acid, bilirubin, coliglyclichiodohistamine, thyroxinglucuronide, penicillin, ß-mercaptoisobutyric acid, dihydroethioctic acid, 6-mercaptopurine, quetoxal-bis (thiosemicarbazone), 1-hydrazinophthalazine (hydralazine) -sulfonylurea, pyridoxylideneglitamate, pyridoxylidene isoleucine, pyridoxylidenephenylalanine, pyridoxylidenetryptophan, pyridoxylidene 5-methyltriptophane, 3-hydroxy-4-formyl- pyriden glutamic, tetracycline, 7-carboxy-β-hydroxyquinoline, phenolphthalexon, eosin a and verografin Optionally, the liposomal construct is also equipped with a masking agent in intimate association with it to protect it from immunoreactive attack, such as for example by macrophages. A preferred embodiment of the present invention then offers a liposomal construct for the administration of serotonin or a serotonergic agonist to the liver of a mammal, comprising a liposomal carrier, serotonin or a serotonergic agonist entrapped within said liposomal carrier or associated with said liposomal vehicle, a molecule attracted by the bile attached to the surface of the liposomal vehicle to bind with a hepatobiliary receptor in the liver, and a sequestering agent within said liposomal vehicle in an amount effective to reduce the leakage of serotonin or liposomal membrane. Optionally, the liposomal construct includes a masking agent in intimate association for the purpose of protecting it from immunoreactive attack. Pharmaceutical compositions of the liposomal constructs are also provided for inducing a serotonergic response in the liver of a mammal, comprising a liposomal vehicle; Serotonin either a serotonergic agonist entrapped within said liposomal vehicle or associated with said liposomal vehicle, a focussing portion attached on the surface of said liposomal vehicle; wherein said focusing portion comprises a molecule attracted by the bile that binds on a hepatobiliary receptor in the liver; a sequestering agent distributed within said liposomal vehicle, said sequestering agent is present in an amount effective to reduce the leakage of serotonin or serotonergic agonist from the liposomal construct prior to administration to the liver, an agent of masking to protect said liposomal vehicle against immunoreactive attack, and a pharmaceutically acceptable excipient. The liposomal constructs and pharmaceutical compositions of this invention are useful for the treatment of disease states that respond to biogenic amines. Such diseases may include, for example, hypertension, shock, heart failure, arrhythmias, asthma, allergy, anaphylaxis, and diabetes. The invention is particularly useful for administering biogenic amines, which, like potent neurotransmitters, must be tightly sequestered within a liposomal construct in order to minimize or substantially eliminate the interactions as receptors of offered organs other than those targeted by the construct. Biogenic amines include sympathomimetic amines, that is, naturally occurring catecholamines and drugs that mimic their action, and autacoids that act as serotonin receptors to elicit a hepatic glucose storage response. See Goodman and Gilman, The P armacological Basis of Therapeutics (the pharmacological basis of therapeutic treatment), ninth edition, Macmillan Publishing Company, (1995). Such neurotransmitters are soluble in water and have a polar nature by maintaining their ability to migrate through liposomal membranes. It is also important that quaternary amines, such as epinephrine and acetylcholine, have a positive charge over a wide pH range, while the remaining neurotransmitters are classified as primary amines and produce only a fully positive charge at a physiological pH and for under the. Since the biogenic amines show a pronounced polarity caused by a positively charged quaternary amine or a primary amino group positively charged at a physiological pH, they demonstrate an unusual aqueous activation and are capable of traversing the liposomal membranes. They are therefore difficult to retain for a certain time within a liposomal core volume. The retention of biogenic amines within a liposomal construct is required not only because of their primary functions but also because they can act in vivo as neurotransmitters and in fact act in vivo as neurotransmitters. Biogenic amines interact with many different cell types and are found in many different cell types, including those that are not necessarily associated with the cell or organ to which the active agent is intended to be administered. These cells include neurons, platelets, mast cells as well as enterochromaffin cells, etc. Accordingly, if a biogenic amine that has been incorporated into a liposome, is not strongly sequestered or retained by the liposomal structure, it may leak from the liposomes and cause undesirable pharmacological responses with other cell types that manifest the same receptors. It is also desirable to employ a "targeted" liposomal vehicle with the present invention. Such targeting can be achieved through the incorporation of antibodies, lectins, peptides, proteins, carbohydrates, glycoproteins, specific hepatobiliary agents and the like on the surface of liposomes. This invention offers several embodiments through which biogenic amines can be effectively conserved or associated with a liposomal construct for an extended period of time in order to prevent their leakage into the external liposomal environment during storage and administration to a host . In one embodiment of the invention, a sequestering agent can be employed which is contained within the core volume of the liposome. In an alternative embodiment, a sequestering agent that is a component of the liposomal carrier membrane can be employed. Suitable sequestering agents are nucleotide derivatives, negatively charged derivatives of dicarboxylic acids such as for example polymers and copolymers of polyamino acids, for example the poly (glutamic-aspartic acid) copolymer. Also, polyphosphate polymers derived from phosphate and phosphatidylphosphate compounds can be used to sequester biogenic amines within a volume of liposomal core. Phosphatidylphosphate derivatives such as phosphatidic acid and phosphatidyl polyphosphate derivatives such as phosphatidyldiphosphate and phosphatidyltriphosphate and phosphatidylinositol 4,5-diphosphate when incorporated as essential constituents of the phospholipid liposomal membrane provide an anionic charge distribution on the inner and outer surfaces. external membrane that not only facilitates the sequestration of biogenic amines but also offers surface charge repulsion between neighboring liposomal vehicles. Any biogenic amine externally sequestered on the liposomal surface can be easily removed by the use of ion exchange chromatography. Other members of the class of polyphosphate compounds that are useful as sequestrants for biogenic amines within the liposomal construct include phytic acid, inositol hexaphosphate, and phosvitin, a phosphate-derived protein that days an esterified phosphate functional group on a serine residue approximately every third amino acid. A particular application of this invention can be illustrated with the hormone and neurotransmitter serotonin. The leakage of a biogenic amine such as serotonin from a liposomal vehicle can cause negative biochemical and physiological side effects since the non-sequestered neurotransmitter has the potential to interact with cellular receptors that are not designed for activation. Thus, a liposomal serotonin leak increases the likelihood of unwanted neurohormonal binding or absorption as well as neurotransiaision. In previous studies such as those described in US 4,761,287, it was shown that to adequately treat non-insulin dependent diabetes mellitus (type II), it is necessary to administer the hormone serotonin to cellular hepatocytes in the liver using a targeted liposomal construct. The administration of this hormone, in combination with the hormone insulin, signals the liver to store blood glucose as glycogen. This action results in the reduction of high circulating glucose levels and decreases the exposure of other tissues and organs in the body to high glucose levels. If the hormone were to leave your vehicle, it would be difficult to administer the correct dosage form to the liver and the intended use of the targeted delivery system would be compromised. Accordingly, in a preferred embodiment, the invention focuses on the retention of biogenic amines such as serotonin and serotonergic agonists within a targeted liposomal construct. If the exogenous serotonin, which has been incorporated into a liposome, is not strongly sequestered or retained by the liposomal structure, then there is a possibility that serotonin will leave the liposomes and cause undesirable pharmacological responses with other types of cells that manifest as receptors. serotonin In a particularly preferred embodiment, the incorporation of the nucleotide adenosine 5'-triphosphate (ATO) into a liposomal core volume facilitates and increases the entrapment or sequestration of biogenic amines. The ATP-serotonin complex is especially interesting. Due to the complexity of the multiple structure of a liposomal vehicle, a biogenic amine, a sequestering agent and, optionally, a targeting molecule, the specific chemical interaction between the nucleotide trapping agent and the positively charged amines remain indeterminate.

It is speculated that within the liposomal construct a complex is formed eg between ATP and serotonin. This association is mediated, it is believed, through the amino terminal group positively charged on serotonin that is ionically bound to phosphate groups negatively charged in ATP resulting in a paired charge interaction at a physiological pH forming a complex with four serotonins by ATP. Other nucleotides may be employed as described above. In addition to the nucleotide compounds, amino acid polymers, such as dicarboxylic acids, aspartic acid and glutamic acid, have been determined as biogenic amine scavengers within a liposomal construct. The copolymeric structure of the aspartic acid covalently linked to the glutamic acid creates an anionic sump that can bind biogenic amines such as serotonin. The liposomal constructs of this invention offer useful agents for pharmaceutical applications for the administration of an active agent to a host. Accordingly, the constructs of this invention are useful as pharmaceutical compositions in combination with pharmaceutically acceptable carriers. The administration of the constructs described herein can be carried out by any of the accepted modes of administration for the biologically active substances that are to be administered. These methods include oral, topical, parenteral, ocular, transdermal, nasal as well as other systemic or aerosol forms. Depending on the mode of administration envisaged, the compositions used can have the solid, semi-solid or liquid dosage form, such as for example tablets, suppositories, pills, capsules, powders, liquids, suspensions or the like, preferably in unit dosages suitable for administration unique of precise dosages. The pharmaceutical compositions will include the liposomal construct in accordance with that described and an acceptable pharmaceutical excipient, and optionally, may include other medical agents, pharmaceutical agents, vehicles, adjuvants, etc. Topical formulations composed of liposomal constructs, penetration enhancers and other biologically active drugs can be applied in many ways. The solution can be applied dropwise, from a suitable administration device, to the appropriate area of the skin or diseased skin or mucosal membranes and manually rubbed or it can be left to simply air dry. A suitable gel-forming agent can be added to the solution and the preparation can be applied to the appropriate area and rubbed. Alternatively, the solution formation can be placed in a spray device and can be administered as a spray. This type of drug administration device is especially well suited for application on large areas of skin, on very sensitive skin, either in the nasal cavity or oral cavity. Parenteral administration is usually characterized by injection, either subcutaneously, intramuscularly or intravenously. Injectable solutions can be prepared in conventional forms, either as liquid solutions or suspensions, solid forms suitable for solution or suspension in liquid before injection, or as emulsions. Suitable excipients are, for example, water, saline, dextrose, glycerol, ethanol or the like. In addition, if desired, the pharmaceutical compositions to be administered may also contain minor amounts of non-toxic auxiliary substances such as for example wetting agent or emulsifiers, pH regulating agents and the like, such as, for example, sodium acetate, sorbitan monolaurate, triethanolamine oleate, etc. The amount of active compound administered will obviously depend on the patient treated, the type of severity of the condition, the manner of administration and the judgment of the physician. further, if the dosage form is intended to provide a prolonged release effect, the total dosage administered will be administered in the total time period of the prolonged release device in order to calculate the appropriate dose required. Although effective dosage ranges for specific biologically active substances of interest depend on several factors, and are generally known to a person with certain knowledge in the art, some dosage guidelines may be generally defined. For most forms of administration, the lipid component will be suspended in an aqueous solution and will generally not exceed 30% (weight / volume) of the total formulation. The drug component of the formulation will probably be less than 20% (weight / volume) of the formulation and generally more than 0. 01% (weight / volume). In general terms, topical formulations are prepared in gels, creams or solutions having an active ingredient within a range of 0.001% to 10% (weight / volume), preferably 0.01 to 5%, and with special preference of about 1% to about 5% (evidently, these ranges are subject to variation depending on the potency of the biogenic amine, and could, under appropriate circumstances, fall within a range as wide as 0.001% to 20%). In all of these exemplary formulations, as well as in other topical formulations, the total dose administered will depend on the size of the affected area of the skin and the number of doses per day. The formulations can be applied as frequently as necessary, but preferably not more than about 3 times a day. For oral administration, a non-toxic, pharmaceutically acceptable composition is formed by the incorporation of any of the excipients normally employed such as for example mannitol, lactose, magnesium star stearate, sodium saccharin, talcum, cellulose, croscarmellose sodium, glucose, gelatin, , sucrose, magnesium carbonate, and the like. Such compositions include solutions, suspensions, tablets, dispersible tablets, pills, capsules, powders, sustained-release formulations and the like. Preferably, the compositions will be in the form of a pill or tablet. Thus, the composition will contain together with the active ingredient: a diluent such as for example lactose, sucrose, diclasic phosphate, or the like; a lubricant such as, for example, magnesium stearate or the like; and a binder such as, for example, starch, acacia gum, gelatin, and polyvinylpyrrolidine, cellulose and derivatives thereof, and the like. Pharmaceutically administrable liquid compositions can, for example, be prepared by dissolution, dispersion, etc. of an active compound in accordance with that defined above and optional pharmaceutical adjuvants in a vehicle, such as, for example, water, saline, aqueous dextrose, glycerol, glycols, ethanol, and the like, to thereby form a solution or suspension. If desired, the pharmaceutical composition to be administered may also contain minor amounts of non-toxic auxiliary substances such as for example wetting agents, emulsifying agents, or solubilizing agents, pH regulating agents and the like, for example, acetate, sodium citrate , cyclodextrin derivatives, sorbitan monolaurate, triethanolamine sodium acetate, triethanolamine oleate, etc. Actual methods of preparing such dosage forms are known, or will be apparent to those skilled in the art; for example, see Remington: The Science and Practice of Pharmacy (Remington: The Science and Practice of Pharmacy), nineteenth edition, 1995 (Marck Publishing Co., Easton, PA). The composition or formulation to be administered will contain, in any way, an amount of active compound, for example, serotonin, in an amount sufficient to effectively treat the disorder or disease of the treated patient. Forms or compositions containing active ingredient can be prepared within the range of 0.005% to 5% with the remainder constituted as non-toxic vehicle. The exact composition of these formulations can vary widely according to the particular properties of the drug in question. However, they will generally consist of 0.01 to 5%, and preferably 0.05% to 1% of active ingredient for very potent drugs, and 2 to 4% in the case of moderately active drugs. In the case of a solid dosage form, the solution or suspension, for example in propylene carbonate, vegetable oils or triglycerides, is preferably encapsulated in a gelatin capsule. Such solutions, and the preparation and encapsulation thereof, are presented in U.S. Patent Nos. 4,328,245; 4,409,239; and 4,410,545. In the case of a liquid dosage form, the solution, for example, in polyethylene glycol, can be diluted with a sufficient amount of pharmaceutically acceptable liquid carrier, for example, water, to be easily measured for administration. Alternatively,. Oral liquid or semi-liquid formulations can be prepared by dissolving or dispersing the active compound or salt in vegetable oil, glycols, triglycerides, propylene glycol esters (eg, propylene carbonate) and the like, and encapsulating these solutions or slurrying them in husks of hard or soft gelatin capsule. Other useful formulations include the formulations presented in U.S. Patent Nos. 28,819 and 4,358, 603. Parenteral administration is usually characterized by injection, either subcutaneously, intramuscularly or intravenously. Injectable preparations can be made in conventional forms, either as liquid solutions or suspensions, solid forms suitable for solution or suspension in liquid before injection, or as emulsions. Suitable excipients are, for example, water, saline, dextrose, glycerol, ethanol, or the like. In addition, if desired, the pharmaceutical compositions to be administered may also contain minor amounts of non-toxic auxiliary substances such as for example wetting agents or emulsifiers, pH regulating agents, solubility enhancers and the like, such as sodium acetate, sorilato monolaurate, triethanolamine oleate, cyclodextrins, etc. A more recently designed approach for parenteral administration employs the implantation of a slow release or prolonged release system, such that a constant dosage level is maintained. See, for example, U.S. Patent No. 3,710,795. The percentage of active compound contained in such parenteral compositions depends to a large extent on the specific nature thereof, as well as the activity of the compound and the needs of the patient. However, percentages of active ingredient from 0.01% to 5% in solution can be employed, and will be higher if the composition is a solid subsequently diluted at the percentages mentioned above. Preferably, the composition comprises 0.2 to 2% of the active agent in solution. Nasal solutions of the liposomal construct alone or in combination with pharmaceutically acceptable excipients can also be administered. Formulations of the liposomal construct can also be administered to the respiratory tract in the form of an aerosol or spray solution, or in the form of a microfine powder for insufflation, alone or in combination with an inert carrier, such as for example lactose. In a case of this type, the particles of the formulation have diameters less than 50 microns, of preferences less than 10 microns. Leaks from prepared liposomes containing a biogenic amine and a sequestering agent can be determined from a conventional stability test, both under storage conditions approaching a controlled storage environment and in physiological fluids, as intended of administration of the liposomal construct. According to the particular application, lipids can be produced which can be loaded by the methods presented herein, and by the methods described in U.S. Patent Nos. 4,946,787; 4,603,044; and 5,104,661, and references cited herein. Typically, the aqueous liposomal formulations of this invention will comprise from 0.01% to 10% of active agent by weight (ie, 100 mg of drug per ml), and from 1% to 20% of lipid by weight comprising a sequestering agent in an amount of 1% to 100% of the lipid component by weight, and an aqueous solution optionally containing salts and regulators, in an amount to constitute 100% by volume. Formulations comprising from 0.1% to 5% active agent and a lipid component comprising a sequestering agent in an amount of 50% or more by weight of the lipid component are especially preferred. A formulation comprising from 1% to 5% active agent by weight, up to 20% by weight of a lipid component, which in turn comprises 10% to 100% by weight of a sequestering agent and an amount of sufficient aqueous solution (qs) to constitute 100% by volume is the most preferred In all these formulations, it is desirable to have a charge ratio between sequestering agent and biogenic amine of at least 1: 1. More preferably, there is at least one residual charge greater than 50% (polymer or non-polymer) versus aminebiogenic, in order to ensure sufficient sequestration efficiency. Example 1. Preparation of liposomes directed against hepatocytes containing a serotonin-ATP complex. Adenosine 5'-triphosphate (ATP) is used as a liposomal sequestrant for serotonin together with the lipid membrane constituents of 69.0 mg of 1,2-distearoyl-sn-glycerol-3-phosphatidylcholine (distearol lecithin) and 14.0 mg of dicetilphosphate both from Avanti Biochemicals; 1.0 mg of N- (2,6-diisopropylphenylcarboylmethyl) imino diacetic acid and 5.0 mg of cholesterol, both from Sigma Chemical Co. The lipid constituents are solubilized in 1.5 ml of chloroform: methanol solvent (2: 1 volume / volume) from Aldrich Chemical Co. The sample is placed in a broken Buchi evaporator and brought to dryness with slow vacuum rotation caused by vacuum cleaner to a temperature of 60 ° C. A solution of 2.4 ml of 40 mM sodium phosphate buffer is then prepared and added to the dry lipid components at a pH of 7.4 freshly prepared containing 4.2 mg / ml of human serum albumin, 10 mg / ml of serotonin and at least 14.4 mg / ml of ATP, all from Sigma Chemical Co. The sample is sonicated in a setting number 4 for 15 minutes at a temperature of 60 ° C, using a HeatSystems Ultrasonic / Cell Disrupter equipped with a transducer and a cup-shaped horn. Then, the sample is tempered at a temperature of 60 ° C with slow rotation for 15 minutes in order to allow the liposomal membranes to become more perfectly formed and more stable. The sample is then centrifuged in a Triac Clinic centrifuge at the blood setting for 15 minutes at room temperature, and then 1.5 ml of the supernatant is chromatographed on a Sephadex G-100-120 1.5 x 25.0 cm column that has been equilibrated with 40 mM of phosphate buffer, pH 7.4 The first chromatography is carried out to remove untrapped serum albumin and the serotonin-ATP complex. The liposomes are collected and, in relation to the initial concentration in N-2, 6-diisopropylphenylcarbamoylmethyl) imino diacetic acid, react with a fivefold modular excess of chromium chloride hydrate. Purified liposomes containing the serotonin-ATP complex reacted with a fivefold molar excess of white N- (2,6-diisopropylphenylcarbamoylmethyl) imino diacetic acid molecules. The liposomes are then chromatographed again using the same regulator in order to remove the unreacted white molecules. The liposomes were stored in nitrogen at a temperature of 5 ° C. These liposomes focused on hepatocytes containing the serotonin-ATP complex are diluted with 40 mM of phosphate buffered saline pH 7.4, before administration to a warm-blooded host. The liposomes are not expected to exhibit a serotonin leak during storage under normal conditions prior to administration to a host animal, in addition, the liposome constructs are not expected to leak significantly when kept in a solution at physiological pH for time periods approaching the times for the demonstration of a physiological effect of serotonin in the liver in the studies described in U.S. Patent No. 4,603,044. The liposome constructs can be administered to a host in the manner described in U.S. Patent No. 4,603,044 and are expected to demonstrate activity in the tests described. Example 2. Methods of high pressure liquid chromatography (HPLC). An Alltech HPLC system with lightning detection was used UV at 230 nm in the following chromatography experiments.

The mobile phase was 5 mM triethylamine pH 4.5 with 90% acetic acid (volume / volume) 10% acetonitrile (volume / volume). The flow rate was 1.0 ml / min. Standard curves of 0-100 ppm at 0-0.1 ppm were developed using injection volumes of lOμl and lOOμl. All the curves presented a linear response. Example 3: Passive charge of 16 hours of 5-hydroxytryptamine creatinine sulfate sulfate (5-HTCS) in liposomes, followed by a leak rate study. A stock solution of 5-hydroxytryptamine creatinine sulfate (5-HTCS) at 1.0 mg / ml (2.58 mM) was made. HDV-D198A is a mixture of lipid constituents dried in an amorphous crust and comprising distearoyl lecithin (DSL), cholesterol (CHOL), dicetyl phosphate (DCP), and Cr- (bis) - [N- (2, 6-diisopropylphenylcarbamoylmethyl) iminodiacetic acid] (crystal). (The vesicles formed from HDV-D198A are vesicles focused towards hepatocytes (HDV), HDV-D198A was added at 1.3 mg of lipid / ml to the 5-HTCS solution and passively charged for 16 hours. chromatography sequences using 20 mM regulator of P04 pH 7.0 and columns PD 10. All fractions were combined, HPLC analysis was performed on fractions and the most concentrated tubes were used for study. 24.7μg / ml of 5-HTCS associated with the liposomal fraction The results appear in the following table: Time Retention in μg of% of total retention in μg 5-HTCS in lipid fraction 2 hours 21.7μg 88.0 4 hours 19.1μg 77.0 18 hours 17.7μg 73.4 Example 4. Active loading of ATP with liposomes 3.6 mg / ml of ATP (6.5 mM) was actively loaded into 20 mM of P04 buffer pH 7.0 with 14.15 mg / ml of HDV-D198A and 50 μl of 1CATP were actively charged with 1.5 minute sonication at a temperature of 60 ° C after 30 minutes of hydration at a temperature of 60 ° C. 1.0 ml of the sample was chromatographed on a Sepharose CL-6B column and 1.5 ml fractions were collected. Results: 24.8μg of ATP were found in 11 tubes containing the lipid fractions. The total ATP recovered was 92.7%. The percentage of ATP associated with the liposomal fraction was 0.7%. Example 5. The passive loading of 5-hydroxytryptamine hydrochloride (5-HTHC1) into liposomes followed by a leak rate study at 2, 16, 40 and 60 hours using white presened liposomes. 10.0 ml of HDV-D198A stock solution were prepared at a rate of 28.3 mg / ml and hydrated at a temperature of 60 ° C for 30 minutes. The sample was then sonicated in aliquots of 1.0 ml for 1.0 minute at a temperature of 60 ° C, size = 79.6 nm. A 6.0 mg / ml stock solution of 5-hydroxytryptamine hydrochloride (5-HTHC1) was prepared and added to the lipid preparation. Equal volumes of 5-HTHC1 and lipid were used. Therefore, the final concentrations were 14.15 mg / ml HDV and 3 mg / ml 5-HTHC1 (14.1 mM) The sample was passively charged for 16 hours Size after mixing = 132.5 n 123.4μg of 5 were found -HTHC1 or 4.11% in the total lipid fraction, tubes No. 8 and No.9 were combined for the leak rate study, 55.7μg of 5-HTHCl / ml were found in the combined sample of the tubes. .8 and No.9 Four chromatography sessions were performed using 1.0 ml aliquots, a short column of Sephadex G25 was equilibrated with 10 mM of 4- (2-hydroxyethyl) -1-piperazineethane sulfonic acid regulator (HEPES), pH 7.0 The 55.7μg of 5-HT HCl / ml of the combined sample of tubes number 8 and number 9 were used to study the leak rate as a function of time.The results appear in the following table: Time Retention in μg of 5-HTHCL% of total still In lipid fraction retained in μg 2 hours 31.2 68.7% 16 hours 31.1 40 hours 22.7 45.9% 64 hours 23.1 47.0% Example 6. Leak velocity study of 5-HT HCl at 2.0 mg of 5-HTHCl / ml (9.45 mM) with lipid concentration at 14.15 mg of lipid / ml using 10 mM of 4- (2-hydroxyethyl) -1-piperaxylethane sulphonic acid regulator (HEPES), pH7.0. 56.6 mg of HDV-D198A were hydrated in 2.0 ml of lOmM of regulator HEPES pH 7.0, at a temperature of 60 ° C for 30 minutes. The concentration of the lipid stock solution was 28.8 mg lipid / ml. 8.0 mg of 5-HT HCl was dissolved in 1900μl of 10 mM of HEPES buffer, pH 7.0. lOOμl of 14C 5-HTCS was added to provide a total volume of 2.0 ml. The concentration of the stock solution of 5-HTHC1 was 4.0 mg of 5-HTHCl / ml. An aliquot of 500μl of a lipid stock solution and 500μl of a stock solution of 5-HTHC1 was added and isonic mixed for 1.0 minute at a temperature of 60 ° C in polycarbonate tubes. The final concentrations were 2.0 mg of 5-HTHCl / ml (9.4 mM) and 14.15 mg of lipid mi. Three separate aliquots of 1.0 ml of sonicated sample were chromatographed on a short G25 Sephadex column. The tubes were combined and a radiochemical analysis was performed. The results appear in the following table: Retention in μg of Itotal in μg of 5-HTHC1% of 5-% of to -HTHC1 in fraction 5-HTHCL retained in HTHC1 such de-lipid in the frac- bine - in 5-HTHC1 li bino lipid tion - recovery ention - rado - μg free after chromathography 300 15.0% 1564 78.2% 93.2% Tube number 4 was used for a leak rate study and had an initial concentration of 84.5 mg of 5-HTHCl / ml. 1.0 ml was chromatographed on a short Sephadex G25 column at selected times to determine a leak rate. The results appear in the following table: Retention time in% of total μg of% of total μg of 5-HTHC1 5-HTHC1 rete- 5-HT- of 5-HTHC1 in fraction - nest in the - HCL recovered of lipid fraction de - in - after lipid, in μg combi - chromatogra free nation 112A 2 hours 67.5 79.0% 10.8% 12.7% 112B 20 hours 54.3 65.2% 23.0% 27.6% 112C 44 hours 49.2 60.4% 25.7% 31.5%% of 5 -HTHC1 recovered after chromatography 112A 92.0% 112B 92.8% 112C 99.1% Tube No. 4 of the sample t = 20 in the table above was chromatographed on a short Sephadex G25 column to see if 5-HT remains associated with lipid. The initial analysis of tube number 4 rebelled the presence of 19.2μg of 5-HTHCl / ml. The results after chromatography appear in the following table: Retention of 5-HTHC1% of the total of μg of in the fraction of -5-HTCH1 retained in lipid, in μg the fraction of lipid 16.8 87.5% Example 7: incorporation of 5- HTHC1 in liposomes using the microfluidizer M-110 1.0613 gm of HDV-D198A were hydrated in 37.5 ml of 10 mM HEPES pH 7.0 regulator (28.3 mg / ml) at a temperature of 60 ° C for 30 minutes using a broken Buchi evaporator. 150 mg of 5-HTHC1 were dissolved in 37.5 ml of 10 M regulator HEPES pH 7.0 (4.0 mg / ml). A stock solution of 5-HTHC1 was added to the lipid stock solution and mixed at a temperature of 60 ° C for 5 minutes to bring it to temperature. The fluidifier was preheated with 150 ml of deionized water at a temperature of 60 ° C and 0.2 μm of milli Q filtered water, and the cut-off pressure was set at 14,000 psig. A mixture of 5-HT lipid was passed through the fluidizer 2 times at a cut-off pressure of 12,000 psig, and at a hydraulic pressure of 60 psig. The preparation was filtered through a 0.2μm acrocap filter using a sterile technique. The sample passed through the filter without difficulty. The final concentration of 5-HTHC1 was 2.0 mg / ml (9.4 mol / ml). The final concentration of HDV was 14.15 mg / ml. The preparation has a translucent appearance with a slight blue color. The loading and retention characteristics for this preparation appear in the following table: Size pH retention% of mg total μg of 5-HT% of 5-HTHC1 in μg, of 5-HTHC1 re HCl in com in combination - of 5- HTHC1 had free fractionation in free - lipid fraction fraction - lipid 76.4 nm 6.0 13.2% 1504 82.1% Size pH% of total 5 - HTHC1 recovered after chromatography 76.4 nm 95.4% additional studies were carried out Leak rate using combined lipid fractions from the initial chromatographs containing 80-82μg of 5-HTHcl / ml. The results of these studies appear in the following table: time μg of retention% of μg total μg of 5-HTHC1 of 5-HTCH1 in - of 5-HTHC1 re in combination fraction of lipid in the free-free fraction of - lipid 2 hours 76 94.8 22. 1 20 hours 56 68.3 33. 8 68 hours 59.3 72.2 33. 8 92 hours 65 71.5 39 116 hours 61 70.1 18 140 hours 50 59.9 36.9 time% of 5-HTHC1 in% of 5-HTHC1 total combination li recovered after chromatography 2 hours 27.2 122 20 hours 41.2 109.5 68 hours 41.1 113 92 hours 42.9 114 116 hours 20.6 90.7 140 hours 44.6 104 Example 8. Replacement of dicetyl phosphate (DCP) in the formulation of HDV liposome with phosphatidic acid (PA) DSL CHOL PA Crystal MW 790 386.7 449 748 Mg 40.8 5.2 12.5 0.7 μmol 51.6 13.4 27.8 0.94 The lipids were dissolved in chloroform: methanol (1: 1 v / v) and dried under high vacuum for one hour. The dried crust was hydrated with 2. Oml of 10 mM HEPES pH 7.0 for 60 minutes at a temperature of 60 ° C to prepare the lipid A stock solution. 20.0 mg of 5-HTHC1 were dissolved in 5.0 ml of 10 mM HEPES pH 7.0 in order to prepare the stock solution of 5-HT B. 500μl of lipid A stock solution was combined with 500μl of 5-HTHC1 B stock solution and pipetted into polycarbonate tubes after being sonicated a temperature of 60 ° C for 1.0 min. Final concentrations: 5-HTHC1 = 2.0 mg / ml (9.4 mol / ml) HDV = 14.15 mg / ml Size = 70.9 pH of the final preparation = 6.2 1.0 ml was chromatographed on a PD-10 column equilibrated in 10 mM HEPEs regulator pH 7.0 tubes 1-6 were combined which comprised the lipid fractions. Tubes 7-30 were combined comprising the free combination of 5- HTHC1. The results obtained for this liposomal construct appear in the following table: μg of retention of% of total μg of μg of 5-HTHC1 in 5-HTHC1 in fraction 5-HTHC1 retained lipid-free combination in the fraction of lipid 205μg 10.25% 1723 μg retention of% of 5-HTHC1 in% of total 5-HTC1 re- 5-HTHC1 in free combination fraction recovered after lipid-chromatography 205μg 86.2% 96.4% Tube 4 of the initial chromatography was then subjected to chromatography in a PD-10 column after 24 hours of incubation at room temperature. The sample initially contained 102μg of 5-HTHCl / ml. μg of retention% of total μg of 5 g of 5-HTHC1% of 5-HTHC1 of 5-HTHC1 in-5-HTHC1 retained in combination in combination-fraction of line in fraction-free free fast of lipid 67μg 65.7 % 32 31.3% μg retention% of 5-HTHC1 total of 5-HTHC1 in - recovered after fraction of chromatography 67 μg 97.0% Example 9: Experiment with phosvitin in order to increase the association 5-HTHC1 with the liposomal fraction. 56.6 mg of HDV-D198A was added to a 25 ml round bottom flask and hydrated with 2.0 ml of 10 mM HEPES regulator pH 7.0 at a temperature of 60 ° C for 30 minutes in order to obtain a lipid stock solution A. 15.6 mg of phosphine plus 20.0 mg of 5-HTHC1 were dissolved in 5 ml of 10 mM HEPEs regulator, pH 7.0 to prepare a stock solution B. 500μl of lipid A stock plus 500μl of stock B were sonicated for 1.0 minute at a temperature of 60 ° C. Final concentrations: Lipid: 14.15 mg / ml 5-HTHC1: 2.0 mg / ml (9.4 mol / ml) Fosvitin: 1.6 mg / ml (9.4 mol / mol) Size: 140.8 nm PH = 6.5 1.0 ml of the final preparation was chromatographed in a PD-10 column balanced in 10 mM HEPES regulator pH 7.0. the results of this experiment appear in the following table: μg of retention of% of total μg of μg of 5-HTHC1 in combi-5-HTHCH1 in fraction 5-HTHC1 retained lipid-free nation in fraction of-lipid 80μg 40% 1512 μg of retention of% of 5-HTHCl in% of 5-HTHC1 total 5-HTHC1 in free combination fraction recovered after lipid chromatography 80μg 75.6% 79.6% Example 10. Experiment with poly (alpha glutamic: alpha-lysine): molar ratio 60:40, MW 23,000 The molecular weight of glutamic residue / lysine was 293.3 (used to calculate the molarity of Glu). 56.6 mg of HDV-D198A were hydrated in 2.0 mg of 10 mM HEPES regulator pH 7.0 at a temperature of 60 ° C for 30 minutes in order to prepare a lipid A stock solution. 4.0 mg of 5-HTHC1 plus 3.0 were dissolved. mg of poly (Glu-Lys) in 2.0 ml of 10 mM HEPES regulator pH 7.0 for stock solution B. 500 μl of lipid A stock solution plus 500 μl of B stock solution were sonicated for 1.0 minute at a temperature of 60 ° C in polycarbonate tubes. Final concentrations: lipid: 14.15 mg / ml 5-HTHC1: 9.4 μmol / ml 5-HT: 2.0mg / ml PolyGlu: 1.5mg / ml PolyGlu: 5.1μmol / ml Size = 117 n PH = 6.4 Chromatography 1.0 ml of the final preparation in a PD-10 column in 10 mM HPES regulator, pH 7.0. the results appear in the following table: μg of retention of% of total μg of μg of 5-HTHC1 in combi-5-HTHCH1 in fraction 5-HTHCl retained lipid-free nation in fraction of-lipid 194μg 9.7% 1650 μg of retention % of 5-HTHC1 in% of 5-HTHC1 total 5-HTHC1 in free combination fraction recovered after lipid chromatography 194μg 82.5% 92.2% The chromatogram of 5-HTHC1 in lipid peak was symmetric. Tube 4 from the initial chromatography containing 106 μg of 5-HTHCl / ml and Poly (Glu-Lys) was chromatographed after 24 hours of incubation at room temperature. 1.0 ml was chromatographed from tube 4 on a PD-10 column in a 10 M HEPES regulator pH 7.0 after 24 hours of incubation at room temperature. The results appear in the following table: μg of retention of% of total μg of μg of 5-HTHC1 in combi-5-HTHCH1 in fraction 5-HTHC1 retained lipid-free nation in fraction of-lipid 64μg 60.4% 40 μg of retention % of 5-HTHC1 in% of 5-HTHC1 total 5-HTHC1 in free combination fraction recovered after lipid chromatography 64μg 37.7% 98.1% Example 11: Passive loading of 6.5 mM 5-HT CS and passive loading of 6.5 mM ATP Na2. 20 mM regulator P04 pH 7.0 concentration of ATP = 3.6 mg / ml (6.5 mM) concentration of 5-HT CS = 2.5 mg / ml (6.5 mM) concentration of HDV liposome = 750 μl of 14.15 mg / ml in 10 ml = 1.06 mg lipid / ml 25 mg of 5-HT and 35.8 mg of ATP were added to 10 ml of 20 mM regulator PO4 pH 7.0. 750 μl of liposomes were added to 10 ml of solution and incubated at room temperature for 97 hours. One ml of solution was subjected to chromatography on a 10 DG column (1.5 x 11.5 cm). Fractions of 1 ml were collected. The most concentrated fraction (tube 5) was preserved for further studies. Time 0: first chromatography - 22.8 μg of 5-HT CS loaded with 22.8 μg of 5-HT CS 2,500 μg of 5-HT CS x 100 = 0.91% associated with the liposomal fraction Time 3.5 hours: second chromatography - 87% preserved (11.4 μg of 13.1 μg in tube 5) Time 16 hours: 52% preserved (6.8 μg of 13.1 μg in tube 5) Example 12: Active loading of 1.0 mM of ATP and active loading of 3. 0 mM 5-HT HCl. 10 mM regulator HEPES pH 7.0 concentration of ATP = 0.55 mg / ml (1 mM) concentration of 5-HT HCL = 0.65 mg / ml (3 mM) concentration of liposome = 14.15 mg / ml concentration of cholesterol oleate (1C) = 50 μl 28.3 mg of HDV-D198A were added to 50 μl of cholesterol oleate (14C) which had been vacuum dried in a 25 ml round bottom flask until toluene evaporated. The lipids were dissolved in 1.0 ml of chloroform: methanol (2.1 volume: volume) and then hydrated with 2 ml of regulator HEPES. The final lipid concentration was 14. 15 mg / ml. The mixture, 1 ml at a time, was subjected to sonication for 30 seconds and then 1.0 ml of an ATP 5-HT solution was added slowly while undergoing sonication for an additional 60 seconds. 3 aliquots of 1.0 ml were separated on a column of CL-6B Sepharose (2 x 20 cm). The two most concentrated fractions were combined. It was chromatographed after time 0 on a PD-10 column (1.5 x 5.5 cm) and collected in 1.0 ml fractions. Time 0: first chromatography - 18 μg of 5-HT HCL loaded or 2.8% of total (0.65 mg / ml), 576 μg free and 1.5 μg of 5-HT HCl found in fraction of ATP (92% justified) Time 3.5 hours : second chromatography - 108% preserved (0.55 μg of 0.51 μg in the combination) Particle size: 110 nm after 1 hour While the invention has been described in relation to the specific modalities presented here, it is understood that modifications thereto and equivalents and variations thereto will be apparent to an expert in the art and are included within the scope of the appended claims.

Claims (14)

1. CLAIMS A liposomal construct for administering a diagnostic or therapeutic agent to a mammal, comprising: a) a liposomal vehicle; b) a diagnostic or therapeutic agent entrapped within said liposomal vehicle or associated with said liposomal vehicle; and c) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of the diagnostic or therapeutic agent from the liposomal construct prior to administration.
2. A liposomal construct according to claim 1 further comprising a targeting portion associated with the surface of said liposomal vehicle; wherein said addressing portion is joined to a receiver associated with a focused site.
3. A liposomal construct according to claim 1 wherein the diagnostic or therapeutic agent is selected from the group consisting of biogenic amines.
4. A liposomal construct according to claim 2 wherein the targeting portion comprises a biliary attraction molecule.
5. A liposomal construct for administering a biogenic amine to liver hepatocytes of a mammal, comprising: a) a liposomal vehicle; b) a biogenic amine trapped within said liposomal vehicle or associated with said liposomal vehicle; c) a linked targeting portion on the surface of said liposomal vehicle; wherein said targeting portion comprises a biliary attraction molecule that binds to a hepatobiliary receptor in the liver; and d) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of the biogenic amine from the liposomal construct prior to administration to the liver.
6. A liposomal construct according to claim 3 or according to claim 5 wherein the biogenic amine comprises a sympathomimetic amine or an autacoid.
7. A liposomal construct according to claim 3 or according to claim 5 wherein the biogenic amine is selected from the group consisting of L-beta-3,4-dihydroxyphenylalanine (L-DOPA), 3- (2-aminoethyl) ) -5- hydroxyindole (5-hydroxytryptamine or serotonin), 2- (4-imidazolyl) ethylamine (histamine), 4- [l-hydroxy-2- (methylamino) ethyl] -1,2-benzenediol (epinephrine), l- [3,4- dihydroxyphenyl] -2-aminoethanol (norepinephrine), gamma-amino-n-butyric acid, acetylcholine, a serotonergic agonist and an amino acid.
8. 8. A liposomal construct according to claim 3 or according to claim 5 wherein the biogenic amine is selected from the group consisting of serotonin and serotonergic agonists.
9. 9. A liposomal construct for administering serotonin or a serotonergic agonist to hepatocytes of the liver of a mammal, comprising: a) a liposomal vehicle; b) serotonin or a serotonergic agonist entrapped within said liposomal vehicle or associated with said liposomal vehicle; c) a linked targeting portion on the surface of said liposomal vehicle; wherein said targeting portion comprises a biliary attraction molecule that binds to a hepatobiliary receptor in the liver; and d) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of the serotonin or serotonergic agonist of the liposomal construct before its administration to the liver.
10. A liposomal construct of any of claims 1, 5 and 9, wherein the sequestering agent is selected from the group consisting of a nucleotide derivative, a polyphosphate derivative, a phosphatidylphosphate derivative, and an amino acid polymer.
11. A liposomal construct according to claim 10 wherein the nucleotide derivative is selected from the group consisting of adenosine 5"-triphosphate (ATP), citidin 5'-triphosphate (CTP), guanosine 5'-triphosphate (GTP), thymidine 5'-triphosphate (TTP), uridin 5'-triphosphate (UTP), adenosine 5'-diphosphate (ADP), citidin 5'- diphosphate (CDP), guanosine 5'-diphosphate (GDP), thymidine 5'-diphosphate (TDP), uridine 5'-diphosphate (UDP), adenosine 5 '-monophosphate (AMP), cytidin 5' -monophosphate (CMP), guanosin 5'-monophosphate (GMP), thymidine 5'-monophosphate (TMP), uridin 5'-monophosphate (UMP), adenosine 5'-tetraphosphate, guanosine 5'-tetraphosphate and thymidine 5'-tetraphosphate.
12. 12. A liposomal construct according to claim 10 wherein the amino acid polymer comprises a copolymer of aspartic acid and glutamic acid.
13. 13. A liposomal construct according to claim 10 wherein the polyphosphate derivative comprises phytic acid or the inositol hexaphosphate and phosvitin.
14. 14. A liposomal construct according to any of claims 4, 5 and 9, wherein the biliary attraction molecule is selected from the group consisting of N- (2,6-diisopropylphenylcarbamoylmethyl) iminodiacetic acid, N- (2, 6-diethylphenyl carbamoylmethyl) iminodiacetic acid, N- (2,6-dimethylphenylcarbamoylmethyl) iminodiacetic acid, N- (4-isopropylphenylcarbamoylmethyl) iminodiacetic acid, N- (4-butylphenylcarbamoylmethyl) iminodiacetic acid, N- (2,3- dimethylphenylcarbamoylmethyl) ) iminodiacetic, N- (3-butylphenylcarbamoyl-methyl) iminodiacetic acid, N- (2-butylphenylcarbamoylmethyl) iminodiacetic acid, N- (4-tertiary-butylphenylcarbamoylmethyl) iminodiacetic acid, N- (3-butoxyphenylcarbamoylmethyl) iminodiacetic acid, acid N- (2-hexyloxyphenylcarbamoylmethyl) iminodiacetic acid, N- (4-hexyloxyphenylcarbamoylmethyl) iminodiacetic acid; substituted azo iminodiacetic acid, iminodicarboxymethyl-2-naphthyl ketone, ftalein complexone, N- (5, pregnen-3-β-ol-2-carbamoylmethyl) iminodiacetic acid, 3a: 7a: 12a: trihydroxy-24-norcholanyl-23-iminodiacetic acid , N- (3-bromo-2,, 6-trimethylphenylcarbamoylmethyl) iminodiacetic acid, benzimidazolmethyliminodiacetic acid, N- (3-cyano-4,5-dimethyl-2, pyrrilcarbaraoylmethyl) iminodiacetic acid, ethylenediamine-N, N-bis (- 2-hydroxy-5-bromo-phenyl) acetate, N'-acyl acid and N '-sulfonyl ethylene diamine N, N diacetic; N'-acetyl EDDA, N'-benzoyl EDDA, N'- (p-toluenesulfonyl) EDDA, N'- (P-t-butylbenzoyl) EDDA, N'- (benzensulfonyl) EDDA, N "- (p-chlorobenzenesulfonyl) EDDA, N '- (p-ethylbenzenesulfonyl) EDDA, N'- (pn-propylbenzenesulfonyl) EDDA, N'- (naphthalene-2-sulfonyl) EDDA, N' - ( 2, 5-dimethylbenzensulfonyl) EDDA; N- (2-acetylnaphthyl) iminodiacetic acid, N- (2-naphthyl) methyl) iminodiacetic acid; rose bengal, congo red, bromosulftaleine, bromophenol blue, phenolphthalein, toluidine blue, indocyanine green, iodipamide, ioglycoamic acid, bilirubin, coligliciliodohistamine, thyroxinglucuronide, penicillin, ß-mercaptoisobutyric acid, dihydroethytic acid, 6-mercaptopurine, quetoxal-bis (thiosemicarbazone); 1-hydrazinophthalazine (hydralazine) -sulfonylurea; pyridoxylideneglitamate, pyridoxylideneisoleucine, pyridoxylidenephenylalanine, pyridoxylidenetryptophan, pyridoxylidene 5-methyltriptophane; 3-hydroxy-4-formyl-pyridenglutamic acid; tetracycline, 7-carboxy-β-hydroxyquinoline, phenolphthalexon, eosin and verografin. A liposomal construct according to any of claims 1, 5, and 9 wherein the liposomal carrier comprises a phosphatidylphosphate derivative. A liposomal construct of claim 15 wherein the phosphatidyl phosphate derivative is selected from the group consisting of phosphatidic acid, phosphatidyldiphosphate, phosphatidyltriphosphate and phosphatidylinositol-4,5-diphosphate. A liposomal construct for administering serotonin or a serotonergic agonist to the liver of a mammal, comprising: a) a liposomal vehicle; b) serotonin or a serotonergic agonist entrapped within said liposomal vehicle or associated with said liposomal vehicle; c) a linked targeting portion on the surface of said liposomal vehicle; wherein said targeting portion comprises a biliary attraction molecule that binds to a hepatobiliary receptor in the liver; and d) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of the serotonin or serotonergic agonist of the liposomal construct before administration to the liver; said sequestering agent comprises a nucleotide derivative selected from the group consisting of adenosine 5-triphosphate (ATP), citidin 5'-triphosphate (CTP), guanosine 5'-triphosphate (GTP), thymidine 5'-triphosphate (TTP), uridin 5'-triphosphate (UTP), adenosine 5'-diphosphate (ADP), citidin 5 '- diphosphate (CDP), guanosine 5'-diphosphate (GDP), thymidine 5'-diphosphate (TDP), uridine 5'-diphosphate (UDP), adenosine 5'-monophosphate (AMP), cytidin 5'-monophosphate (CMP), guanosine 5'-monophosphate (GMP), thymidine 5'-monophosphate (TMP), uridin 5'-monophosphate (UMP), adenosine 5'-tetraphosphate, guanosine 5'-tetraphosphate and thymidine 5'-tetraphosphate. A liposomal construct according to any of claims 4, 5, 9 and 17 wherein the biliary attraction molecule is selected from the group consisting of substituted iminodiacetic acids, N'-substituted derivatives of ethylenediamine-N, N-diacetic acid ( EDDA), hepatobiliary dyes, hepatobiliary contrast agents, bile salts, hepatobiliary linden complexes, as well as hepatobiliary complexes (including hepatobiliary amine complexes). A liposomal construct according to any of claims 5, 9, and 17 further comprising a masking agent in intimate association therewith to protect said liposomal construct against immunoreactive attack. A pharmaceutical composition comprising a liposomal construct of any of claims 1, 5, 9, and 17 and a pharmaceutically acceptable excipient. A pharmaceutical composition for inducing a serotonergic response in the liver of a mammal, comprising: a) a liposomal carrier; b) serotonin or a serotonergic agonist entrapped within said liposomal vehicle or associated with said liposomal vehicle; c) a linked targeting portion on the surface of said liposomal vehicle; wherein said targeting portion comprises a biliary attraction molecule that binds to a hepatobiliary receptor in the liver; d) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of the serotonin or serotonergic agonist of the liposomal construct before administration to the liver; e) a masking agent in intimate association to protect said liposomal carrier against immunoreactive attack; and a pharmaceutically acceptable excipient. A method for the treatment of a disease state in a mammal in response to a therapy with biogenic amines, said method comprising administering a therapeutically effective amount of a composition of claim 5 to the mammal. A method for the treatment of type II diabetes in a mammal, said method comprises administering a therapeutically effective amount of a pharmaceutical composition of any of claims 9, 17, or 21 to the mammal. A method for the treatment of type II diabetes in a mammal, said method comprises administering a therapeutically effective amount of a pharmaceutical composition, comprising: a) a liposomal vehicle; b) serotonin or a serotonergic agonist entrapped within said liposomal vehicle or associated with said liposomal vehicle; c) a linked targeting portion on the surface of said liposomal vehicle; wherein said targeting portion comprises a biliary attraction molecule that binds to a hepatobiliary receptor in the liver; d) a sequestering agent distributed within said liposomal vehicle, said sequestering agent being present in an amount effective to reduce the leakage of serotonin or serotonergic agonist from the liposomal construct before administration to the liver; e) a masking agent in intimate association to protect said liposomal carrier against immunoreactive attack; and a pharmaceutically acceptable excipient. A method according to claim 24 wherein the amount of serotonin is from about 100 to about 200 μg.