28289-54-5

Human toxicity originally discovered when it was an unexpected by-product from the illicit synthesis of a heroin substitute (i.e., meperidine analog). Currently used experimentally as the primary animal model for the study of Parkinson’s disease. MPTP is a neurotoxicant that is activated to 1-methyl-4-phenylpyridinium ion (MPP1) by the actions of monoamine oxidase B located in the mitochondria of brain astrocytes. The MPP1 is then transported into dopamine, and to a lesser extent, other monoaminergic neurons. Once inside these dopamine neurons in the substantia nigra, it destroys these neurons by mechanisms that may involve an oxidative cascade and/or inhibition of electron transport. Intoxication causes a parkinsonism syndrome almost identical in signs and symptoms to Parkinson’s disease, including rigidity, bradykinesia, tremor, and postural instability. In the event of known ingestion, immediate (but not delayed) administration of a monoamine oxidase inhibitor (especially one selective for MAO-B like deprenyl) and dopamine uptake inhibitor can be therapeutic.