[Effects of chronic Semax administration on exploratory activity and emotional reaction in white rats].

Effects of chronic intranasal administration of ACTH(4-10) analog Semax (MEHFPGP) on exploratory activity, anxiety level, and depression-like behaviour were studied in white rats. The peptide was injected daily in dose 0.05 mg/kg during 10 or 14 days. It was shown that chronic Semax administration at 1-2 weeks induced anxiolytic and antidepressant effects but did not influenced the exploratory activity in non-stressogenic environment. The Semax effects may be the results of activation of the brain serotoninergic system as well as increased BDNF expression in the rat hippocampus.