[Effect of neuropeptide fragments of adrenocorticotropic hormone and vasopressin on the behavioral activity of rats].

The effects of vasopressin and those of fragments of adrenocorticotropin ACTH5-10; ACTH4-7; l-phenilalanin, and ACTH4-7 d-phenilalanin on the learning of rats in U-shaped labyrinth were studied. The consolidation of skills in long-term memory ability for reversal learning were checked. The results suggest that effect of all these oligopeptides on the higher nervous activity is significant and specific, vasopressin improving the long-term memory, ACTH4-7-l-phenilalanin improving the learning, ACTH4-7-d-phenilalanin making learning next to impossible.