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janet paterson wrote: > > Common garden, pet pesticide linked to Parkinson's disease > > Monday 6 November 2000 > > A widely used pesticide found in flea powders and plant sprays <<<<<<<<< BIG SNIP >>>>>>>>>>>>> for your information from ray strand the abyss is white with snow threw a letter of resignation over the edge today sad and relieved stepping forward and not going back ---------------------------------------- here is something from a few years ago off of pub med --------- 1990!!!! rotenone link to pd not new ---------------------------------------- : FEBS Lett 1990 Nov 12;274(1-2):1-8 Mechanism of the neurotoxicity of MPTP. An update. Singer TP, Ramsay RR Department of Biochemistry-Biophysics, University of California, San Francisco 94143. This review summarizes advances in our understanding of the biochemical events which underlie the remarkable neurotoxic action of MPTP (1-methyl-4-phenyl-1-1,2,3,6-tetrahydropyridine) and the parkinsonian symptoms it causes in primates. The initial biochemical event is a two-step oxidation by monoamine oxidase B in glial cells to MPP+ (1-methyl-4-phenylpyridinium). A large number of MPTP analogs substituted in the aromatic (but not in the pyridine) ring are also oxidized by monoamine oxidase A or B, is in some cases faster than any previously recognized substrate. Alkyl substitution at the 2'-position changes MPTP, a predominantly B type substrate, to an A substrate. Following concentration in the dopamine neurons by the synaptic system, which has a high affinity for the carrier, MPP+ and its positively charged neurotoxic analogs are further concentrated by the electrical gradient of the inner membrane and then more slowly penetrate the hydrophobic reaction site on NADH dehydrogenase. Both of the latter events are accelerated by the tetraphenylboron anion, which forms ion pairs with MPP+ and its analogs. Mitochondrial damage is now widely accepted as the primary cause of the MPTP induced death of the nigrostriatal cells. The molecular target of MPP+, its neurotoxic product, is NADH dehydrogenase. Recent experiments suggest that the binding site is at or near the combining site of the classical respiratory inhibitors, rotenone and piericidin A. Publication Types: Review Review literature PMID: 2253761, UI: 91071405