The effect of chronic treatment of deprenyl in animal models of Parkinson's disease

Recent studies have demonstrated that deprenyl can delay the progression of parkinsonian syndrome. Deprenyl selectively and irreversibly inhibits the activity of monoamine oxidase-type B (MAO-B), and subsequent enzyme activity requires de novo synthesis of MAO-B. In this study we investigated (1); the effects of deprenyl on striatal dopamine (DA) levels in MPTP-lesioned and undamaged mice and (2); the effect of deprenyl on L-DOPA induced rotational movements in a hemiparkinsonian model monkey. In MPTP-lesioned mice, deprenyl increased the striatal DA levels by 123%, 78% immediately and one week after termination of deprenyl treatment respectively, while by 31%, 24% in MPTP-undamaged mice, respectively. Four weeks after termination of treatment, and the striatal DA was not significant. It shows that deprenyl is effective in elevation of striatal DA at least one week after termination of treatment, and the degree of increase of striatal DA following deprenyl treatment is greater in MPTP-treated mice than in undamaged mice. Deprenyl seemed to be effective longer in a hemiparkinsonian monkey than in rodents. The result suggests that less frequent administration of deprenyl may be effective in controlling side effects of L-DOPA without reducing therapeutic efficacy.