Carbon dioxide production by red skeletal muscle of goldfish (Carassius auratus L.) aerobic and anaerobic metabolism of glucose and glutamate.

Oxygen uptake and metabolic CO2 production by lateral red muscle of goldfish have been measured in vitro. Added glucose 6-phosphate depresses the rate of oxygen uptake by minced red muscle (Crabtree effect). Total CO2 production is stimulated resulting in a respiratory quotient which is considerably greater than one. 14CO2 release from [U-14C] glucose 6-phosphate and [U-14C] glutamate continues during anoxia. No activity of the hexose monophosphate shunt was observed. The results suggest that both aerobic and anaerobic CO2 production is of mitochondrial origin and, at least partially, derived from TCA cycle reactions.