Effects of Cortisone and Hydrocortisone on Sodium Excretion in Adrenalectomized Rats

Summary

1. The influence of time and dosage upon sodium excretion by rats was investigated after cortisone and hydrocortisone administration. 2. Results of time-response studies show that large doses cause initially weak and transient retention of sodium and subsequently strong excretion of the ion. Smaller doses reduce progressively duration of retention phase and hasten onset of secondary diuresis. 3. Two factors appear to influence the response of sodium excretion. During a fixed time-interval of urine collection, increasing doses cause excretion, no change and retention of sodium. Similar changes in excretion of the ion are seen with a given dose when collection interval is progressively shortened.