Humoral factors and the sodium-potassium pump in low renin hypertension.

Recent studies suggest that sodium dependent low renin hypertension results in part from the release of a ouabain-like factor, perhaps natriuretic hormone, from the brain. This humoral factor inhibits Na+, K+-ATPase and hence the active pumping of sodium and potassium in the muscle cells of blood vessels and heart. The pump suppression causes increased contractile activity and hence increased arterial blood pressure. In the muscle cells of the blood vessels, the increased contractile activity appears to be related to membrane depolarization.