Hepatic Enzyme Activities in Rats Made Diabetic with Alloxan and with Guinea Pig Anti-insulin Serum

In diabetes abnormally high rates of gluconeogenesis have been demonstrated by various methods. Here it is confirmed that in rats which have been fasted or treated with alloxan, changes occur in hepatic enzyme activity which are compatible with an adaptation to increased rates of gluconeogenesis; there are increased glutamic-pyruvic and glutamic-oxalacetic transaminase and glucose-6-phosphatase activities and reduced lactic dehydrogenase activity. Comparable effects were demonstrated in the livers of rats killed in a diabetic state twenty-four to sixty hours after injection of guinea pig anti-insulin serum, with the exception that glutamic-pyruvic transaminase activity was not increased and glutamic-oxalacetic transaminase activity was increased when expressed per liver protein or per body weight, but there was no change in the activity of the total liver. This finding provides suggestive evidence that increased gluconeogenesis is also characteristic of this experimental diabetic syndrome produced by anti-insulin serum.