Mg2+ inhibition of Na2+-stimulated Ca2+ release from brain mitochondria.
Magnesium has been shown to modulate the Na+-stimulated release of Ca2+ (Na/Ca exchange) from brain mitochondria. The presence of 5 mM MgCl2 extramitochondrially inhibits the Na/Ca exchange as much as 70%. Additionally, Na+-stimulated Ca2+ release is enhanced by the presence of divalent chelators, this stimulation also being inhibited by the addition of excess Mg2+. The inhibitory effect of Mg2+ and the enhancement by chelating agents were both reversible. Heart mitochondria exhibit a similar enhancement of Na/Ca exchange by chelators and inhibition by MgCl2, though not as pronounced.
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D005971:Glutamates / Q000378:metabolism; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D008293:Malates / Q000378:metabolism; D008297:Male; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D012964:Sodium / Q000494:pharmacology*
D005971:Glutamates; D008293:Malates; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D004533:Egtazic Acid; D004492:Edetic Acid; D012964:Sodium; D008274:Magnesium; D002118:Calcium