Effects of Ca2+ on the activities of the calcium-sensitive dehydrogenases within the mitochondria of mammalian tissues.
Three important dehydrogenases in the mitochondria of mammalian tissues are activated by Ca2+ ions: these are pyruvate dehydrogenase, NAD-isocitrate dehydrogenase, and oxoglutarate dehydrogenase. Evidence is summarized that when hormones and other extracellular stimuli increase the cytoplasmic concentration of Ca2+ in rat hearts and livers that this results in a parallel rise in the intramitochondrial concentration of Ca2+. In this way, pyruvate oxidation and citric acid cycle flux are stimulated and there is an increase in NADH supply for the respiratory chain under conditions where there is an enhanced demand for ATP.
Denton
R M
RM
Department of Biochemistry, University of Bristol School of Medical Sciences, England.
Rutter
G A
GA
Midgley
P J
PJ
McCormack
J G
JG
D000818:Animals; D002118:Calcium / Q000502:physiology*; D006801:Humans; D008928:Mitochondria / Q000201:enzymology*; D010088:Oxidoreductases / Q000378:metabolism*
D010088:Oxidoreductases; D002118:Calcium