EFFECT OF ACTG(4-7)-PRO-GLY-PRO AND ACTG(6-9)-PRO-GLY-PRO ON THE INTENSITY OF REDOX PROCESSES AND BEHAVIOURAL STATUS OF RATS UNDER THYROID HYPERFUNCTION CONDITIONS

Abstract

The aim of the work is to study the effect of melanocortins on the intensity of redox processes in the prefrontal region of the brain and the behavioral status of rats against the background of thyroid hyperfunction. Material and methods. In the experiment, the test animals were divided into the following groups (n = 10): intact rats (control); animals treated with sodium salt pentahydrate L-thyroxine (hyperthyroidism); rats receiving ACTH (4-7)-Pro-Gly-Pro and individuals receiving ACTH (6-9)-Pro-Gly-Pro, re-spectively, intraperitoneally daily for 21 days, starting from day 22 of administration of sodium salt pentahydrate L-thyroxine. Hyperthyroidism was simulated in animals by intragastric administration of L-thyroxine sodium salt pentahydrate for 42 days. The intensity of lipoperoxidation processes was studied by the content of diene and triene conjugates in the prefrontal zone tissue, the initial level of TBА-reactive products, and the rates of spon-taneous and ascorbic peroxidation of lipids. The level of protein peroxidation products was determined by the reaction of oxidized amino acid residues of proteins with 2,4-dinitrophenyl hydrazone. Evaluation of the enzymatic unit of the antioxidant system of the prefrontal region was carried out by de-termining the activity of superoxide dismutase and catalase. The behavioral status of laboratory rodents was studied using the «Hole board» test. Results. The use of ACTH(4-7)-Pro-Gly-Pro and ACTH(6-9)-Pro-Gly-Pro compounds under experimental hyperthyroidism led to a decrease in the intensity of the processes of peroxidation of lipids, proteins and the restoration of levels of activity of antioxidant enzymes – superoxide dismutase and catalase in the tissue of the prefrontal region of the brain of animals, as well as correction behavioral indicators in the «Hole board» test. Conclusion. The obtained experimental data indicate that ACTH(4-7)-Pro-Gly-Pro and ACTH(6-9)-Pro-Gly-Pro show antiperoxy and antioxidant activity against lipoperoxidation parameters and oxidative modification of proteins and enzymatic protection systems in the prefrontal brain zone tissue, as well as exert psychocorregating action on behavioral responses of white rats against the background of thyroid hyperfunction.