Stimulation by calcium and other cations of the cholesterol binding to steroid-free cytochrome P-450scc purified from bovine adrenocortical mitochondria: the implication of ACTH-mediated calcium homeostasis on the cholesterol availability.
By utilizing purified cytochrome P-450scc from bovine adrenocortical mitochondria and cholesterol-containing dioleoylglycerophosphocholine liposomes, we have demonstrated a dramatic stimulation (2-3 fold) of cholesterol binding to the steroid-free cytochrome by Ca++. We theorize that ACTH modulates the increase of intracellular Ca++ concentration resulting in the increase of the cholesterol availability to the mitochondrial cytochrome.
D000302:Adrenal Cortex / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology*; D002417:Cattle; D002784:Cholesterol / Q000378:metabolism*; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000378:metabolism; D006706:Homeostasis; D007700:Kinetics; D008081:Liposomes; D008928:Mitochondria / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D011485:Protein Binding; D013053:Spectrophotometry
D008081:Liposomes; D000324:Adrenocorticotropic Hormone; D002784:Cholesterol; D002786:Cholesterol Side-Chain Cleavage Enzyme; D011188:Potassium; D002118:Calcium