Effects of Adrenal Medullary Hormones on Renal Excretion of Water and Electrolytes

Abstract

Subcut. injns. of nor-epinephrine in doses of 33 ug./100 g. body wt. to intact water-hydrated rats caused an increase in: (a) serum Na concn.; (b) Na and Cl excretion; (c) urine flow; (d) GFR; (e) hematocrit, and an insignificant increase in systolic blood pressure. Nor-epinephrine caused a decrease in urinary K concn. Epinephrine in the same dose had no effects in these respects. In saline loading, nor-epinephrine caused an increase in urine flow and a decrease in the urinary concn. of Na, Cl and K; epinephrine caused a decrease in urine flow and an increase in the urinary concn. of Na. Epinephrine caused significant depletions of adrenal ascorbic acid, whereas, nor-epinephrine caused little, or no change, in adrenal ascorbic acid. Thus, in small doses, the adrenal medullary hormones influence water and electrolyte excretion by acting upon tubular and possibly glomerular kidney function.