These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine- and 1-methyl-4-(2'-ethylphenyl)-1,2,3,6-tetrahydropyridine-induced toxicity in PC12 cells: role of monoamine oxidase A. Author: Basma AN, Heikkila RE, Nicklas WJ, Giovanni A, Geller HM. Journal: J Neurochem; 1990 Sep; 55(3):870-7. PubMed ID: 2384758. Abstract: The toxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-(2'-ethylphenyl)-1,2,3,6-tetrahydropyridine (2'Et-MPTP), and their corresponding pyridinium species was studied in the rat pheochromocytoma PC12 cell line. MPTP and its analogues are known to be metabolized by monoamine oxidase (MAO) to dihydropyridinium intermediates which are further transformed, either enzymatically or spontaneously, into pyridinium species. MAO activity in PC12 cells is almost exclusively of the A form, and 2'Et-MPTP is a good substrate for both MAO-A and MAO-B. In contrast, MPTP is a poor substrate for MAO-A, but a good substrate for MAO-B. 2'Et-MPTP caused considerably more cell death than MPTP in the PC12 cells. However, 1-methyl-4-(2'-ethylphenyl)pyridinium and 1-methyl-4-phenylpyridinium, the corresponding pyridinium species formed from 2'Et-MPTP and MPTP, respectively, were equipotent as toxins. The toxic effects of the tetrahydropyridines and their corresponding pyridiniums were both concentration- and time-dependent. Measurements of the levels of the pyridinium species formed and the remaining tetrahydropyridine in the media indicated that 2'Et-MPTP was converted about five to seven times more readily into its toxic pyridinium species than was MPTP. There was, moreover, an excellent correlation between amount of pyridinium formed and cell death. There was also a parallel between the capacity of clorgyline and pargyline, irreversible MAO inhibitors, to decrease the formation of the pyridinium species and their capacity to protect against the toxic actions of the tetrahydropyridines. These data are consistent with the concept that the MAO-A-dependent formation of the pyridinium species from the tetrahydropyridine is a prerequisite for toxicity in PC12 cells.[Abstract] [Full Text] [Related] [New Search]