[Effect of ACTH4-10 on the behavior of mice]

The effect of 40 mcg/kg i. p. injections of ACTH4-10 were investigated in C57BL/6J mice. Peptide injections caused a significant (p less than 0,05) decrease in rearing activity frequencies as well as a decrease in defecation and grooming levels. ACTH4-10 accelerated the acquisition of conditioned food-motivated running reaction and also induced significant resistance against extinction of this habit. The ability of mice to solve the task of extrapolating the direction of stimulus movement was nonsignificantly reduced at the first task presentation and in the total experiment. The ACTH4-10 ability to facititate stereotype reactions is one of possible mechanisms of behaviour changes in the present experiments.