Reninlike activity in kidneys of dogs with neurogenic and nephrogenic hypertension

Abstract

Reninlike activity in dog kidneys was measured using a simple but reliable procedure that involved injection of saline extracts of portions of renal cortex into nephrectomized assay rats. In dogs with neurogenic hypertension the amount of pressor material in the renal cortex was within the normal range. In dogs with one kidney wrapped in cellophane the opposite untouched kidney became almost completely depleted of pressor material despite no appreciable rise in arterial pressure. Both findings support the hypothesis that a humoral factor, presumably of renal origin, is more important than systemic arterial pressure in determining the amount of pressor material in the kidney. As groups, dogs made hypertensive by cellophane perinephritis, or by constricting a renal artery and contralateral nephrectomy, showed an increase in reninlike activity in the manipulated kdiney, but in individual experiments there was no correlation between the amount of pressor activity and the level of the arterial pressure.