Rats from two strains with opposite constitutional predisposition to hypertension were joined in parabiosis and one partner was nephrectomized. The influence of genetic factors and of diet on the blood pressures of the two classes of parabionts, operated and intact, indicated that renoprival hypertension occurred with equal frequency in rats from both strains; that the development of renoprival hypertension depended on the influence from an intact S partner, or on a high salt intake, or on both.
A nephrectomized S rat developing renoprival hypertension did not induce high blood pressure in its intact R partner. In this respect renoprival hypertension differs from salt and renal hypertension.
The findings are interpreted to mean that the hypertensinogenic agent specific for S rats is produced by S kidneys.