The effects of a competitive prolyl endopeptidase inhibitor benzyloxycarbonyl-alanyl-proline were studied in rats with experimental dopamine deficiency-dependent depressive syndrome due to systemic administration of a proneurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine for 14 days. The inhibitor was injected intraperitoneally 30 min before treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (2nd week of the study). This substance contributed to rapid disappearance of depressive symptoms during the recovery of behavioral activity. Our results indicate that benzyloxycarbonyl-alanyl-proline has the antidepressant properties.
