Rate of Change in Sodium and Potassium Excretion After Injection of Aldosterone Into the Aorta and Renal Artery of the Dog

Abstract

The rate of change in sodium and potassium excretion and reabsorption following the intra-arterial injection of single 2-, 5- or 10-µg doses of aldosterone was compared with the effect of similar doses injected directly into one renal artery, in nine adrenalectomized female mongrel dogs off replacement therapy for 48 hours. After a delay of 5–30 minutes, the hormone produced decreased sodium and increased potassium excretion, and a rise in sodium and a fall in potassium reabsorbtion associated with no consistent change in glomerular filtration rate. The magnitude of the response was greater with larger doses but the onset and rate of development of the changes were not changed. Direct injection into the renal artery produced changes which did not differ in their timing or magnitude from the effects of the same doses injected intra-arterially. The effect on the uninjected kidney was not significantly different from that on the injected side. PSP and Pitressin produced more profound effects on the injected side.