Study of immunotropic activity of the valine-containing neuropeptide compound of the glyprolin series under “social” stress

Aim of the study was to investigate the immunotropic activity of neuropeptide compound Pro-Gly-Pro-Val under “social” stress.
Material and methods. The study was conducted on nonlinear male rats (6 months old) under conditions of “social” stress, modeled by formation of submissive and aggressive types of animal behavior under conditions of constant sensory contact. The rats were divided into groups: Control I, animals housed alone in a cage and receiving water for injection in an equivalent volume; Control II, groups of stressed animals with aggressive and submissive types of behavior; III groups of stressed rats to which Pro-Gly-Pro-Val at a dose of 100 μg/kg/day; IV groups of stressed rats to which imunofan (Arg-Asp-Lys-Val-Tyr-Arg) at an average therapeutic dose of 0.7 μg/kg/day were administered intraperitoneally. The immunotropic properties of the neuropeptide compounds were evaluated according to the following indices: delayed-type hypersensitivity reaction index, direct hemagglutination reaction antibody titer and leukocytic formula values.
Results. Injection of the tested compound Pro-Gly-Pro-Val under study leads to correction of the immune changes occurring against the background of “social” stress, namely, to an increase in the delayed-type hypersensitivity reaction index and the level of anti-erythrocytic antibodies, to an enhancement in the total leukocyte count and a restoration of the percentage ratio between the form elements of the leukocytic formula. Obtained results correlate with the results of studying the immunotropic action of the comparison preparation immunofan under the conditions of “social” stress.
Conclusions. The results of the study of the immunotropic action of the neuropeptide compound Pro-Gly-Pro-Val under “social” stress indicate the presence of its immunocorrective activity, which is manifested by the restoration of indices of cellular and humoral reactions and white blood cells.

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