Reninlike activity in kidneys of rats with various types of experimental hypertension.

Renal pressor activity was measured in rats with the different types of experimental hypertension using a direct method for the evaluation of the role of the renal pressor material in the production and the maintenance of high blood pressure. Renin content was increased in the constricted kidney and decreased in the contralateral of renal hypertension, and also decreased in adrenal regeneration hypertension. In coarctation of aorta and neurogenic hypertension, renin content in the kidneys was within normal range. High blood pressure could be maintained independently of an increase in renin concentration of the kidneys. Renal renin content seems likely the result of the sodium situation of animals and the circulation in one kidney. It still remains possible that a small change in renin formation and secretion, not detectable by the present method, might affect the reactivity of the vascular smooth muscle to the sympathetic neurohumoral agent.