Acute effects of 1-methyl-4-phenylpyridinium ion (MPP+) on dopamine and serotonin metabolism in rat striatum as assayed in vivo by a micro-dialysis technique.
The acute effect of 1-methyl-4-phenylpyridinium ion (MPP+), a neurotoxin derived from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), was examined by the in vivo micro-dialysis technique. A dialysis cannula was implanted into rat striatum, and the changes in the concentrations of dopamine (DA), 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in the perfusate every 20 min after administration of MPP+ were determined by high-performance liquid chromatography with electrochemical detection (HPLC-ED). After MPP+ administration the levels of DOPAC, HVA and 5-HIAA were markedly decreased. On the contrary the level of DA was markedly increased and reached a maximum 40 min after beginning of the MPP+ administration. By postmortem analysis of the striatal tissue MPP+ was proved to cause the inhibition of monoamine oxidase (MAO), especially MAO-B. These results suggest that the acute biochemical changes induced by MPP+ in vivo were MAO inhibition and release of DA.
D015655:1-Methyl-4-phenylpyridinium; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003342:Corpus Striatum / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism; D009498:Neurotoxins / Q000032:analysis / Q000494:pharmacology*; D011726:Pyridinium Compounds / Q000032:analysis / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*
D009498:Neurotoxins; D011726:Pyridinium Compounds; D012701:Serotonin; D008995:Monoamine Oxidase; D015655:1-Methyl-4-phenylpyridinium; D004298:Dopamine