Blood sugar after injection of acetoacetate.

A number of investigators (1) have attempted to explain the decreased utilization of carbohydrate in conditions accompanying food intakes low in carbohydrate and high in fat. In the case of the formation of increased amounts of ketone bodies due to such conditions or to diabetes, Nath and Brahmachari (2) have attributed at least a part of the decreased utilization of carbohydrate to an inactivation of available insulin by these intermediary fat metabolism products. “Insulin-refractory” cases were explained in this way. They also reported (3) that repeated injections of acetoacetic, @hydroxybutyric, and pyruvic acids caused hyperglycemia in rabbits, with fasting values increasing from day to day after daily injections. We had previously noted (4,5) that rats which had been on a low proteinhigh fat diet were much more susceptible to ketosis when fasted and that they also exhibited a decreased glucose tolerance. In view of the above findings, it seemed desirable to obtain additional information regarding the effect of the ketone bodies on carbohydrate metabolism in such animals. When rats instead of rabbits were used as the experimental animal, we failed to confirm the findings of Nath and Brahmachari. Instead of elevated blood sugar levels, hypoglycemia developed after the injection of very large amounts of acetoacetate.