title: Possible participation of membrane thiol groups on the mechanism of NAD(P)+-stimulated Ca2+ efflux from mitochondria.
abstract: NAD(P)+-stimulated Ca2+ efflux from mitochondria is inhibited by bongkrekate and slightly stimulated by carboxyatractylate. Addition of oxaloacetate, an NAD(P) oxidant, or diamide, a thiol oxidant, to de-energized mitochondria incubated in Ca2+ -free medium induced a small decrease in turbidity of the mitochondrial suspension compatible with small structural changes of mitochondria. Similar to NADP+-stimulated Ca2+ efflux these changes were also inhibited by bongkrekate and slightly stimulated by carboxyatractylate. The similarity between the effects of oxaloacetate and diamide, on both Ca2+ efflux and mitochondrial structure, indicates the existence of a common denominator, possibly the oxidation of specific thiol groups, regarding the mechanism by which these agents stimulate Ca2+ efflux from mitochondria.
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000818:Animals; D001278:Atractyloside / Q000031:analogs & derivatives / Q000494:pharmacology; D001865:Bongkrekic Acid / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects; D003958:Diamide / Q000494:pharmacology; D008930:Mitochondria, Liver / Q000378:metabolism*; D009249:NADP / Q000494:pharmacology*; D010071:Oxaloacetates / Q000494:pharmacology; D010084:Oxidation-Reduction; D051381:Rats; D013438:Sulfhydryl Compounds / Q000378:metabolism*
chemical_list: D010071:Oxaloacetates; D013438:Sulfhydryl Compounds; D003958:Diamide; D001865:Bongkrekic Acid; D001278:Atractyloside; D009249:NADP; D000244:Adenosine Diphosphate; C003853:carboxyatractyloside; D002118:Calcium