| Abstract: | Cholesterol side-chain-cleavage enzyme activity in mitochondria isolated from heavily luteinized rat ovaries was determined using isocitrate as an electron donor and [4-14C]cholesterol to start the reaction. The activity of the enzyme was reduced when more than 10 microM calcium was added to the mitochondrial preparations. When 100 microM EGTA or 2 mM ATP was added to the reaction an increase in enzyme activity was observed and ATP was able to partially overcome the calcium-induced inhibition. |
