Activities of prolyl endopeptidase and dipeptidyl peptidase IV in brain structures of rats with dopamine deficiency-dependent MPTP-induced depressive syndrome.

The development of MPTP-induced depressive syndrome in rats was accompanied by activation of prolyl endopeptidase and dipeptidyl peptidase IV in the brain frontal cortex. Prolyl endopeptidase activity in the striatum also increased under these conditions. Our results indicate that proline-specific peptidases in the target structures of the brain dopaminergic system are involved in the pathogenesis of dopamine deficiency-dependent depressive states.