Chemically induced Parkinson's disease. II: Intermediates in the oxidation and reduction reactions of the 1-methyl-4-phenyl-2,3-dihydropyridinium ion and its deprotonated form.
The one-electron reduction product of 1-methyl-4-phenyl-2,3-dihydropyridinium ion has been generated by pulse radiolysis and its absorption spectrum recorded. This radical was found to decay by second-order kinetics (2k = 9.5 x 10(8) M-1 s-1) to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 1-methyl-4-phenyl-2,3-dihydropyridinium ion. Reactions of the above radical species and that formed by one-electron reduction of 1-methyl-4-phenylpyridinium ion, which can also be generated by one-electron oxidation of 1-methyl-4-phenyl-1,2-dihydropyridine, with a number of molecules of biochemical interest have been studied. The one-electron reduction product of oxidised nicotinamide adenine dinucleotide efficiently reduced 1-methyl-4-phenyl-2,3-dihydropyridinium ion (k = 2.2 x 10(9) M-1 s-1). The relevance of these results in relation to redox cycling, a possible mechanism for 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxicity, is discussed.
Department of Chemistry, Paisley College, Scotland, U.K.
J N
JN
Chacón
M R
MR
Chedekel
E J
EJ
Land
T G
TG
Truscott
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D004583:Electrons; D006801:Humans; D007202:Indicators and Reagents; D007700:Kinetics; D010084:Oxidation-Reduction; D010302:Parkinson Disease, Secondary / Q000139:chemically induced*; D010782:Photolysis; D011725:Pyridines / Q000633:toxicity; D011726:Pyridinium Compounds / Q000633:toxicity; D013053:Spectrophotometry
D007202:Indicators and Reagents; D011725:Pyridines; D011726:Pyridinium Compounds; C044755:1-methyl-4-phenyl-2,3-dihydropyridinium; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine