Adenine nucleotides regulate Ca2+ transport in brain mitochondria.
Adenine nucleotides (ADP greater than ATP) greatly enhance Ca2+ uptake and retention in rat brain mitochondria. In the presence of both spermine and ADP, brain mitochondria sequester Ca2+ down to cellular free Ca2+ levels, suggesting a role for mitochondria in modulating Ca2+ cycles in brain cells. Analysis of the effects of various inhibitors on Ca2+ uptake and efflux suggest that locking the ADP/ATP translocator in its M-state stimulates electrogenic Ca2+ uptake and, to a lesser extent, inhibits Ca2+ efflux. It is suggested that this effect is due to a modulation of the surface charge on the M-side which enhances Ca2+ dissociation from the carriers.
Rottenberg
H
H
Pathology Department, Hahnemann University, Philadelphia, PA 19102.
Marbach
M
M
D000244:Adenosine Diphosphate / Q000494:pharmacology*; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D001278:Atractyloside / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D001865:Bongkrekic Acid / Q000494:pharmacology; D001921:Brain / Q000378:metabolism* / Q000648:ultrastructure; D002118:Calcium / Q000378:metabolism*; D004533:Egtazic Acid / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism*; D000226:Mitochondrial ADP, ATP Translocases / Q000037:antagonists & inhibitors / Q000378:metabolism; D051381:Rats; D013096:Spermine / Q000494:pharmacology
D001865:Bongkrekic Acid; D001278:Atractyloside; D013096:Spermine; D004533:Egtazic Acid; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000226:Mitochondrial ADP, ATP Translocases; D002118:Calcium