JPS61271226A - Diuretic agent - Google Patents

Abstract

PURPOSE:A diuretic agent consisting of a complex of albumin with a hydrophobic loop diuretic agent. CONSTITUTION:A diuretic agent obtained by incorporating albumin (obtained by purifying directly a raw material blood plasma) with a hydrophobic loop diuretic agent (hydrophobic organic acid based diuretic agent containing furosemide, ethacrynic acid, bumetamide, etc.) at 1:1-1:5 molar ratio in a suitable solvent, e.g. sodium hydroxide reagent, physiological saline solution or phosphate-buffered saline (PBS) to give a complex, and incorporating the resultant complex therein, and having thermal stabilizing effect on albumin. The heat treatment of this albumin complex can be carried out under given conditions (60 deg.C for 10hr). In the heat treatment, the above-mentioned complex is characterized in that the amount of the given stabilizer can be reduced when the linked diuretic agent, particularly >=3mol, based on the albumin, diuretic agent is present. The administration is carried out using 0.3-1mg/kg expressed in terms of the furosemide by intravenous injection.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel diuretic, more specifically, a novel diuretic consisting of a complex of a loop diuretic such as furosemide, ethacrynic acid, bumetanide, etc., which are known as strong diuretics, and albumin. Regarding drugs.

Traditionally, powerful diuretics such as furosemide have been frequently used to improve edema in patients with heart failure and nephrotic syndrome.

These patients often have low protein levels, hypoalbuminemia, and sometimes significant diuretic resistance.

Therefore, when diuresis needs to be applied immediately to patients with heart failure or pulmonary edema, large doses of six diuretics are administered.
Problems of various side effects arise. For example, large doses of furosemide are often associated with side effects such as serum electrolyte abnormalities and hearing loss.

In addition, the diuretic effect of these diuretics is due to the diuretic effects on blood plasma proteins,
In particular, it is based on the binding property with albumin, and it is known that in patients with hypoalbuminemia, that is, when the albumin concentration in the blood is low, the binding property of the diuretic with albumin decreases, and the diuretic effect is also significantly reduced. There is. For this reason, in these patients with hypoalbuminemia, the above-mentioned diuretics and albumin preparations are used in combination. For example, [l
fmJ*&@ Volume 5, No. 12, 251-255 (
(December 1981) described that as a treatment for childhood nephrotic syndrome, the combination administration of albumin and various diuretics such as hydrochlorothiazide, spironolactone, furosemide, etc. improved edema and increased urine output. There is. However, in these conventional combination administrations of albumin and diuretics, they are generally administered separately, as in the literature, albumin is injected intravenously and then diuretics are injected orally, intramuscularly, or intravenously. The dose of Ano 1/Pumin is a large amount, such as 0.5 to 1 g/moan/day. As is well known, albumin preparations are expensive because they are derived from human plasma, which is limited in raw material, and the use of large quantities is a burden to patients.

The present inventors previously investigated the in-vivo dynamics of diuretics, particularly furosemide, and serum albumin using albumin-free rats, and clarified the influence of the albumin-furosemide binding on the diuretic effect. , 13th
Volume 3, No. 5, 311-312. May 1985).

The present invention further advances this research, and shows that when a complex is formed between a loop diuretic and albumin before administration and this complex is administered, unexpected effects are obtained, especially in the amount of albumin used. It has been found that the desired diuretic effect can be obtained with a significantly smaller amount than the amount normally used for separate administration, and it is therefore possible to obtain a sufficient edema-improving effect.

In addition, albumin preparations must be heat-treated (60°C for 110 hours) to prevent contamination with pathogens such as hepatitis viruses, and at that time albumin 3.0 is used as a stabilizer.
Acetyltryptophan sodium 15m per 3mM
M or acetiμ sodium tryptophan/sodium caprylate 3mM each (total 16mM) is used. In this study, the present inventors found that these stabilizers inhibit the binding of albumin and diuretics, and surprisingly, when loop diuretics themselves form a complex with albumin, albumin It was found that it has a thermal stabilizing effect.

Therefore, according to the present invention, there is provided a novel diuretic consisting of a complex of a loop diuretic and albumin-7, and as a further preferred embodiment, a complex of albumin and loop diuretic with a substantially reduced amount of conventional stabilizers. A novel diuretic agent is provided which comprises a complex with an agent.

The loop diuretics used in the present invention include hydrophobic organic acid diuretics including furosemide, ethacrynic acid, pumetanide, and the like.

As the albumin used in the present invention, ordinary commercially available albumin preparations are sufficient to achieve its purpose, but when preparing a complex with a reduced stabilizer content, one purified directly from raw plasma is used. . Purification can be carried out by conventional ethanol fractionation, dealcoholization, etc.

The preparation of a complex of albumin and a loop diuretic can be carried out by combining both with a suitable solvent such as sodium hydroxide reagent, physiological saline,
It can be formed by mixing in PBS or the like in an appropriate ratio, preferably at a molar ratio of 1:1 to 1:5. The heat treatment of the present albumin complex can be conventionally performed under predetermined conditions (60° C., 10 hours). During this heat treatment, the complex of the present invention has the advantage that the amount of a given stabilizer can be reduced due to the presence of a bound diuretic, particularly when the diuretic is present in an amount of 3 moles or more relative to albumin. For example, in conventional albumin preparations, the amount of sodium acetyltryptophan alone or a stabilizer consisting of sodium caprylate required for heat treatment is equivalent to 5.3 mol per 1 mol of albumin, but according to the present invention, it is 3 mol or less. Or it can be reduced almost to zero.

The reaction mechanism for complex formation is known and non-covalent. Whether or not a complex is formed can be easily determined by methods such as equilibrium dialysis, centrifugal filtration, and high performance liquid chromatography.

The diuretics of the present invention can generally be administered intravenously as cifurosemide in an amount of about 0.3 to 1 mg/9.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 Using a commercially available furosemide injection solution (Lasix ■, manufactured by Hekinuto) and an algumi 720% preparation (manufactured by Kaketsuken), 0.125 mg of furosemide was obtained! The mixture was mixed at a ratio of 32 μl of fulbumin (molar ratio 1:1) and incubated at 25° C. for 10 minutes. After that, centrifugal filtration was performed, and the amount of residual furosemide in the filtrate was determined by high-performance chromatography.

When measured, more than 98% of furosemide was bound to albumin.

The diuretic effect of the albumin-furosemide complex prepared as described above was investigated as follows. For furosemide, the above-mentioned commercially available injection solution was used.

First, to examine the diuretic effect of furosemide alone, normal rats (body weight aoog) and albumin-free rats (body weight 400 g) were tested.
g) Furosemide 0.5) was administered intravenously, and post-administration urine was collected every 10 minutes using Cheetair under Bendoparviter 7 anesthesia. The results are shown in Figures 1 and 2. In normal rats, a remarkable diuretic effect was observed immediately after administration, whereas in albumin-free rats, no change in urine volume was observed after administration of furosemide.

Next, the albumin=70semide complex prepared above was intravenously injected into albumin-free rats (0.0% as furosemide).
(5 mg/kp), marked transient diuresis was observed (see Fig. 2, left side).

Furthermore, when albumin-furosemide complexes prepared according to Example 1 at various ratios were administered to albumin-free rats (body weight 250 g), furosemide was administered after administering the same amount of albumin as the amount of albumin in each complex. In this case, the dose of furosemide was 0.5 mg/kf for both complex administration and separate administration, and urine output was measured at 1.
I went after 0 minutes. As is clear from Figure 3, in the case of administration of albumin-furosemide complex, a significant diuretic effect is observed, whereas in the case of pre-administration of albumin, no significant diuretic effect is observed even if the amount of albumin increases. Almost no diuretic effect was observed with albumin alone.

Example 2 The following experiment was conducted to investigate the binding property between albumin and furosemide and the influence of an albumin heat stabilizer on this binding property.

First, five kinds of albumin solutions were prepared as follows from albumin obtained by subjecting raw human plasma to ethanol/l/fractionation and dealcoholization in a conventional manner.

C...A with a standard amount of sodium caprylate added Using each of the above albumin solutions and the furosemide solution used in Example 1, the molar ratio of furosemide/albumin was 0.25, respectively. 0.5.1.2.3.4 and incubated at room temperature for 10 minutes to prepare a solution containing each complex. Filtrate OD measurement after ultrafiltration of each liquid (using Centricon manufactured by Amicon) ODaao
) to determine the concentration of free furosemide in the filtrate.

The amount obtained by subtracting this free amount of furosemide from the initial amount of furosemide is defined as the amount of furosemide bound to albumin.
The ratio of the amount of bound furosemide to the amount of free furosemide (bound furosemide/free furosemide) was expressed as the binding ability of albumin to furosemide. FIG. 4 is a plot of the measurement results for each sample.

This result clearly shows that the presence of the stabilizer reduces the above-mentioned binding ability. However, as is clear from the comparison of the curve and E, no decrease in binding ability was observed due to heating.

Example 3 The following experiment was conducted to examine the thermal stability of the albumin-furosemide complex.

The albumin solution A of Example 2 and the furosemide solution were mixed in various proportions, and then treated with varying amounts of sodium acetyltryptophan or sodium chloride (in PBS) as a stabilizer and heat-treated at 6°0C for 10 hours. The results are shown in Tables 1 and 2, and it can be seen that the albumin-furosemide complex of the present invention has a sufficient heat stabilizing effect even when the amount of a conventional stabilizer is reduced.

Furthermore, the furosemide/albumin ratio -1) 17.5
The precipitation in the above cases is considered to be the precipitation of furosemide itself, which has not bound to the albumin solution.

Table 1 Table 2* ← = Gelling + = More than cloudy As is clear, the albumin-loop diuretic complex of the present invention can be used in patients with hypoalbuminemia when the conventional diuretic, albumin, is separately administered. compared to when
It brings about an extremely effective diuretic improvement effect, and as a result, it is expected to sufficiently improve edema and increase blood protein concentration. Furthermore, it is truly surprising that the amount of heat stabilizer of albumin, which reduces the binding capacity of alepmin-diuretics, can be reduced by the present invention.

Furthermore, according to the principles of the present invention, not only the above-mentioned diuretics, but also
The present invention is also fully applicable to hydrophobic drugs that can be transported to specific organs by binding to albumin in the blood.

[Brief explanation of drawings]

FIG. 1 is a graph showing the normal diuretic effects of conventional diuretics in normal rats. FIG. 2 is a graph comparing the diuretic effects of a conventional diuretic and a diuretic according to the present invention in albumin-free rats. FIG. 3 is a graph showing the diuretic effect in albumin-free rats when conventional diuretics and albumin are administered separately. FIG. 4 is a graph comparing the 9-potency of albumin with Toquino 70 semide in which an albumin heat stabilizer was present in the albumin-diuretic complex of the present invention. 1 amount (ml/IC) yj'

Claims (3)

[Claims] (1) A diuretic consisting of a complex of albumin and a hydrophobic loop diuretic. (2) The diuretic according to claim (1), wherein the loop diuretic is furosemide, ethacrynic acid, or pumetanide. (3) The diuretic according to claim (2), wherein the loop diuretic is furosemide.