Experimental Renal Hypertension: Renin Content of Kidneys in Intact and Adrenalectomized Rats Given Cortexone

The effects were investigated in rats of unilateral renal ischemia, adrenalectomy and varying doses of cortexone on the development of hypertension and on the content of pressor substances in the kidney. Adrenalectomy prevented the hypertension which follows unilateral clamping of the renal artery when a life maintaining dose of 0.1 mg cortexone acetate was injected daily. However, administration of 75 mg cortexone in the form of implants restored but did not enhance the characteristic hypertensive response to renal ischemia. The characteristic distribution of renal pressor material, being normal in the clamped and diminished in the contralateral kidney, was no longer observed after adrenalectomy when only small doses of cortexone were given but was still evident when excess cortexone was given. Overdosage with cortexone without clamping a renal artery led only to a moderate reduction of pressor material in both kidneys while in animals with unilateral renal ischemia the pressor material (renin?) in the contralateral kidney disappeared completely. Clamping the renal artery prevented the diminution of pressor material in the ipsilateral kidney which otherwise occurs under overdosage with cortexone in the normal animal.