Effect of Anti Parkinson drug HP-200 (Mucuna pruriens) on the central monoaminergic neurotransmitters.

Manyam BV, Dhanasekaran M, Hare TA.


Department of Neurology, Scott & White Clinic and Texas A & M University System Health Science Centre College of Medicine, Temple, TX 76508, USA.


HP-200, which contains Mucuna pruriens endocarp, has been shown to be effective in the treatment of Parkinson's disease. It has also been shown to be more effective, compared to synthetic levodopa in an animal model of Parkinson's Disease.

The present study was designed to elucidate the long-term effect of Mucuna pruriens endocarp in HP-200 on monoaminergic neurotransmitters and its metabolite in various regions of the rat brain.

HP-200 at a dose of 2.5, 5.0 or 10.0 g/kg/day was mixed with rat chow and fed daily ad lib to Sprague-Dawley rats (n = 6 for each group) for 52 weeks. Controls (n = 6) received no drug. Random assignment was made for doses and control. The rats were sacrificed at the end of 52 weeks and the neurotransmitters were analysed in the cortex, hippocampus, substantia nigra and striatum.

Oral administration of Mucuna pruriens endocarp in the form of HP-200 had a significant effect on dopamine content in the cortex with no significant effect on levodopa, norepinephrine or dopamine, serotonin, and their metabolites- HVA, DOPAC and 5-HIAA in the nigrostriatal tract.

The failure of Mucuna pruriens endocarp to significantly affect dopamine metabolism in the striatonigral tract along with its ability to improve Parkinsonian symptoms in the 6-hydorxydopamine animal model and humans may suggest that its anti Parkinson effect may be due to components other than levodopa or that it has a levodopa enhancing effect.