Effects of adrenalectomy, aldosterone and dehydration on electrolyte metabolism of rat renal cortex slices

¹ Department of Medicine and Biochemistry, Peter Bent Brigham Hospital and Harvard Medical School, Boston, Massachusetts

An attempt has been made to study the action of aldosterone on tubular reabsorption of sodium using in vitro incubation of rat renal cortex slices. In normally hydrated animals neither adrenalectomy nor aldosterone, whether injected into the animal or added to the incubation medium, influenced significantly the rate and extent of slice sodium and water accumulation and potassium depletion. However, effects on other variables were found. After adrenalectomy, the oxygen consumption of the renal cortical tissue was decreased 10–13.5% and the ammonia production 27–33%. Unlike oxygen consumption, ammonia production was influenced by aldosterone; when the hormone was injected into rats the renal cortical ammonia production increased 27–65%. Ammonia concentrations in the incubation media could account for the progressive alkalinization observed with increasing time of incubation. Hydropenia resulted in an increased sodium accumulation and potassium depletion, and a decreased oxygen consumption and ammonia production by incubated slices from intact as well as adrenalectomized rats.