[Influence of Semax on the emotional state of white rats in the norm and against the background of cholecystokinin-tetrapeptide action].

The effects of the adrenocorticotropic hormone (ACTH(4-10)) analog, Semax (MEHFPGP), on the level of anxiety and depression in white rats have been studied in the normal state and against the background of cholecystokinin-tetrapeptide (CCK-4) action. Semax was injected intranasally in doses of 50 and 500 microg/kg 15 min before the testing. CCK-4 was administered intraperitoneally in a dose of 400 microg/kg 40 min before the testing. The level of anxiety was estimated in the elevated plus-maze test, and the degree of depression, in the forced swimming test. Semax administration did not influence the emotional state of animals in the normal state. The CCK-4 injection led to an increase in anxiety and depression in rats. Semax normalized the animal behavior disturbed by the CCK-4 administration, which attests to its anxiolytic and antidepressant effects at elevated levels of anxiety and depression.