Noun

1. A byproduct of synthetic heroin, or MPPP, which causes Parkinsonian symptoms in users.
2. A neurotoxin which degrades into MPP+ after crossing the blood brain barrier, which causes a degredation of the dopaminergic neurons within the substantia nigra.

Quotations

• 2005 Dec 29 Petzinger, et al. Journal of Neuroscience Research http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16385585&query_hl=8&itool=pubmed_docsum

  The neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine MPTP provides an excellent opportunity to study repair and response to injury in the basal ganglia.