Genetic Influence of the Kidneys on Blood Pressure

Abstract

In two strains of rats with opposite genetic propensities for hypertension, interstrain renal transplants chronically modified the blood pressure of the recipients. The blood pressure of rats with these renal homografts was largely determined by the genotype of the donor kidney rather than by the genotype of the recipient. Kidneys from the hypertension-resistant (R) rats generally had an antihypertensive effect, and kidneys from the hypertension-prone (S) rats had a prohypertensive effect. These effects on blood pressure were most clear-cut in rats maintained on a low-sodium diet, but they were still evident in a modified form in rats on a high-sodium diet. Results from this study and from earlier studies suggest that kidneys from S rats have a greater hypertensinogenic and a smaller antihypertensive capacity than do kidneys from R rats. Therefore the influence of the kidney on blood pressure appears to have genetic determinants. If this finding is applicable to man, it would help to explain the well-established but anomalous observation that one of two individuals who apparently have similar renal disorders can have hypertension when the other does not.