Structural transformations of thermal burn wounds in rats under the influence of Semax and Selank neuropeptides

Abstract

The morphological features of the skin of rats under the stress exposure, such as burn injury and against the background of the correction by the drugs of the peptide structure, have been studied.The aim of the study was to investigate the regulatory effect of the neuropeptide drugs Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) under the conditions of thermal burn exposure.Materials and methods. The object of the study was integumentary tissues (skin, subcutaneous tissue) of laboratory non-linear male rats (n = 36) excised from the thermal injury zone. A thermal burn of the skin had been caused by the application of a copper object in the interscapular in the interscapular dorsal area. Starting from the first day after the injury, neuropeptide drugs Semax (Met-Glu-His-Phe-ProGly-Pro) and Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) had been administered intraperitoneally at the doses of 100 μg/kg daily during the entire period of the experiment. To assess the condition of the skin tissues, histological sections 5–6 μm thick were prepareв, stained afterwards with hematoxylin and eosin. The consistency of the systemic effect of the neuropeptide drugs was estimated by a change in some indicators of the immune system.Results. The thermal exposure led to the development of significant degenerative and dystrophic changes in the skin. The recovery of the burn wounds on rats’ skins proceeded according to the type of the delayed partial reparative regeneration, accompanied by destructive phenomena and the formation of the scar tissue.Under the influence of the drugs based on the regulatory peptides of Semax (Met-Glu-His-Phe-Pro-Gly-Pro) and Selank (Thr-Lys-Pro-Arg-ProGly-Pro), the recovery of burn wounds in rats proceeded more intensively, compared with the animals from the group without any correction. This fact was confirmed by the earlier signs of the beginning of the reparative skin regeneration: the restriction of destructive processes within the epidermis and dermis, the absence of purulent-necrotic complications, the initial phases of granulation and epithelization, an early scab rejection and a partial closure of the defect.Conclusion. The use of the neuropeptide drugs Semax and Selank as systemic remedies for the correction of wound skin defects in experimental animals proves their polypotent effectiveness, expands the therapeutic possibilities and opens up new prospects for their use.