THE EFFECT OF d -ALDOSTERONE AND SPIRONOLACTONE ON THE CONCENTRATION OF SODIUM AND POTASSIUM IN THE MILK OF RATS

SUMMARY The effects of d-aldosterone and spironolactone on the sodium and potassium concentrations in the milk of rats were determined. d-Aldosterone caused a highly significant fall in the milk sodium concentration and the Na:K ratio when compared with control animals. The administration of spironolactone shortly before aldosterone gave results not significantly different from control animals. It is concluded that aldosterone has a specific sodium-lowering action in the milk of the lactating rat.