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.