title: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine inhibits proton motive force in energized liver mitochondria.
abstract: It is known that 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which induces Parkinson's-like disease in primates and humans, depletes hepatocytes of ATP and subsequently causes cell death. Incubation of rat liver mitochondria with MPTP and 1-methyl-4-phenyl pyridinium ion (MPP+) significantly inhibited incorporation of 32Pi into ATP.MPTP and MPP+ inhibited the development of membrane potential and pH gradient in energized rat liver mitochondria, suggesting that reduction of the proton motive force may have reduced ATP synthesis. Since deprenyl, an inhibitor of monoamine oxidase, prevented the formation of MPP+ and inhibited the decrease in membrane potential caused by MPTP, but not that caused by MPP+, these effects of MPTP, as well as cell death, probably were mediated by MPP+. This mechanism may play a role in the specific loss of dopaminergic neurons resulting in MPTP-induced Parkinson's disease.
authors.affiliation: Section on Drug Tissue Interaction, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892.
authors.forename: Y
authors.initials: Y
authors.lastname: Singh
authors.forename: R
authors.initials: R
authors.lastname: Bhatnagar
authors.forename: G S
authors.initials: GS
authors.lastname: Sidhu
authors.forename: J K
authors.initials: JK
authors.lastname: Batra
authors.forename: G
authors.initials: G
authors.lastname: Krishna
mesh_terms: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D015655:1-Methyl-4-phenylpyridinium; D000200:Action Potentials / Q000187:drug effects; D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D009498:Neurotoxins / Q000494:pharmacology*; D011522:Protons; D011725:Pyridines / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D011726:Pyridinium Compounds / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012642:Selegiline / Q000494:pharmacology
chemical_list: D009498:Neurotoxins; D011522:Protons; D011725:Pyridines; D011726:Pyridinium Compounds; D012642:Selegiline; D000255:Adenosine Triphosphate; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D015655:1-Methyl-4-phenylpyridinium