RU2384892C1 - Method for modelling atrophic skin scar - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention is related to experimental medicine, namely to experimental dermatology and can be used for modelling atrophic skin scar. That is ensured by single dosing of 0.2 ml of collagenase of the content at least 100 KE for the whole length of a needle of an insulin syringe parallel to the skin surface with smooth drawing of the needle and uniform pressure upon a syringe piston.

EFFECT: method provides adequate reproducibility of atrophic skin scar, reduced time of modelling with simplicity of implementation.

4 dwg, 1 ex

Description

The present invention relates to medicine, namely to dermatology, and can be used to study the processes of formation of atrophic scars, their correction and degenerative processes in the dermis.

The prototype of the present invention is a method for modeling atrophic scars, which consists in creating a linear defect of all layers of the skin, including subcutaneous fat, by 5-cm incision with a surgical scalpel and fixing the defect by introducing a plastic frame into the lumen of the formed wound in order to prevent contraction, which after 7 days removed, after which the wound was closed with sterile napkins (Zolotovitskaya N.V., author. for the degree. Candidate of Medical Sciences. Moscow, 2007, p.6-7). The disadvantage of this technique is the complexity of the experiment, its multi-stage and duration of scar formation - 28 days.

The objective of the invention is the development of a pathogenesis-related formation of atrophic scars in the clinic, technically simple to implement, easily reproducible method for modeling atrophic skin scars.

The technical result when using the invention is to simplify and shorten the formation of atrophic skin scar.

The specified technical result is achieved by the fact that in the method of modeling an atrophic scar of the skin according to the invention, 0.2 ml of a collagenase solution with a content of at least 100 KE is introduced once into the thickness of the reticular dermis parallel to the skin surface in a tunneling-retrograde manner.

A method for modeling an atrophic skin scar is as follows. As experimental animals use white rats. Produce mechanical depilation of the skin of the back of the animal. Then, within one hour, exposure to level local irritation, which may be caused by mechanical action during depilation. Under local application anesthesia (Emla cream, holding for 15 minutes under an occlusal film), parallel to the skin surface, along the spine, at a distance of 2 cm from it, an insulin syringe needle is inserted into the thickness of the reticular layer of the dermis. The needle length is 1.6 cm, the diameter is 0.40 G. To comply with the conditions for introducing the needle to the required depth, visual inspection is performed - the needle should be clearly contoured when it is raised, but the surface of the needle (its color) should not be visible. Then, using a tunneling-retrograde method, with a smooth pulling of the needle and uniform pressure, 0.2 ml of a collagenase solution with a content of at least 100 KE is injected onto the syringe plunger (for example, Collalizin, dilution of 500 KE in 1 ml). Under the action of collagenase, a lysis of the area of the connective tissue component of the skin is realized, which simulates the formation mechanism minus tissue in case of acne and other inflammatory skin diseases. As a result, a linear atrophic scar defect forms in the area of projection onto the skin surface of the intradermally injected volume of the collagenase solution. A pronounced atrophic defect is formed within 7-10 days.

To assess the reliability of the results of the proposed method for modeling an atrophic skin scar, dermatoscopy was performed with photo documentation. The technique was tested on 15 rats. Animals were kept in a vivarium in accordance with the Sanitary Rules for the Design, Equipment and Maintenance of Experimental Biological Facilities (Vivariums), approved by the Ministry of Health of the USSR on 07/06/1973 and order of the Ministry of Health of the USSR No. 163 of 03/10/1966. Work on rats was carried out in accordance with with the principles of humane treatment of experimental animals, approved by order of the Ministry of Health of the USSR No. 755 of 08/12/1977 and No. 701 of 07/27/1978.

The proposed method is illustrated by the following drawings.

Figure 1 shows that in the injection zone of the drug after 15 minutes, the appearance of infiltration, hemorrhagic staining of the skin over the injection site is noted.

Figure 2 shows that after 1 hour there is a maximum swelling and hemorrhage at the injection site.

Figure 3 shows that on the 3rd day of the experiment, a scar was formed with a hemorrhagic crust above it.

Figure 4 shows the formed atrophic scar after the discharge of the crust on the 8th day.

The proposed method allows to determine the stage of formation of atrophic skin scars, which allows experiments to treat them at different stages of formation.

The proposed method is illustrated by the following example: a rat, a male of the Wistar strain, weighing 250-300 g, under local application anesthesia, into the thickness of the reticular dermis parallel to the skin surface by a tunneling-retrograde method, 0.2 ml of a collagenase solution containing 100 KE was injected once using insulin syringe. On the 8th day, an atrophic scar was formed on the skin surface in the area of the projection of the path of collagenase administration onto it.

Claims (1)

A method for modeling atrophic skin scars, characterized in that 0.2 ml of a collagenase solution with a content of at least 100 KE is introduced once into the thickness of the reticular layer over the entire length of the needle of the insulin syringe parallel to the skin surface with smooth pulling of the needle and uniform pressure on the syringe plunger.

Images