Influence of adrenalectomy on glucose turnover and conversion to CO2: studies with C14 glucose in the dog

Abstract

In view of the small glucose pool size and turnover rate observed in the untreated hypophysectomized dog and the elevation of these parameters after administration of the 11, 17-oxycorticosteroids, experiments were performed to determine glucose pool size and turnover rate in the unanesthetized adrenalectomized dog in the postabsorptive state. The adrenalectomized dog has a glucose pool of nearly normal size and has a nearly normal rate of glucose flow from the liver into the plasma and from the plasma into the tissue cells. Expiration of C14O2 during the C14 glucose experiments was observed in normal and adrenalectomized dogs and is interpreted on the basis of a three-compartment pool of body bicarbonate as deduced from the C14O2 expiration curve following intravenous injection of HC14O3–. Most adrenalectomized and some normal dogs have a pattern of C14O2 excretion which indicates that glucose upon entering tissue cells either goes promptly to CO2 or is directed into pathways such that its carbon does not become CO2 later on in the course of a 5-hour experiment. The C14O2 data show no clear difference between the normal and the adrenalectomized dog with regard to the conversion of glucose to CO2.