Studies of Fasted, Water-deprived Intact and Adrenalectomized Dogs Injected with Glucocorticoids.

SummaryAdrenalectomized dogs deprived of food for 48 and water for 24 hours respond to injections of prednisolone by as marked an increase in plasma volume as observed in similarly fasted intact dogs. Desoxycorticosterone when given simultaneously with the glucocorticoid does not potentiate the plasma volume-raising action of the latter. Massive doses of prednisolone (315 mg) induced striking elevation of the plasma volume of dogs fasted 72 hours and deprived of water for 48 hours, despite excretion of 740 ml of fluid as urine. Blood sugar and plasma Na also increased but the hemoglobin and hematocrit fell sharply. Fasted but non-injected adrenalectomized dogs reacted quite differently. They exhibited drastic decline in plasma volume and blood sugar whereas hemoconcentration increased. The fluid mobilized to increase the plasma volume apparently was shifted from the intracellular compartment under influence of the hormone which is somehow concerned with active transfer of sodium and water across cellular ...