Differential effects of deprenyl and MPTP on catecholamines and activity in BALB/c mice.

The present study examined the effects of deprenyl (1.5 mg kg-1) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (30 mg kg-1) on dopamine (DA), norepinephrine (NE) and motor activity in BALB/c mice. Results indicate that pre-treatment with deprenyl injections protected against MPTP's toxicity on DA, NE and motor function. However, if deprenyl was given 3 or 7 days after the MPTP injection (for 3 days in succession), it could not reverse MPTP's toxicity. However, if deprenyl was given for an extended period of 7 days, it reversed MPTP's toxicity on NE, but not on DA and behaviour. If deprenyl was given soon after MPTP each day for 10 days, it protected against MPTP's toxicity on DA and NE, but not on locomotor activity. These results suggest that only prior and repeated deprenyl injection has a satisfactory protective effect against MPTP's neurotoxicity.