Leptin and the renin-angiotensin-aldosterone system.

Abstract

To the Editor: Shek et al1 recently reported in a very detailed study that chronic leptin infusion in rats increased mean arterial blood pressure. However, the mechanism of leptin-induced hypertension is unclear and may involve both central and peripheral actions. While the sympathoexcitatory action of leptin is well established and may be a major factor mediating its hypertensive effect,1 2 the role of leptin in another major regulator of blood pressure, the renin-angiotensin-aldosterone system, has yet to be defined. Shek et al provide the first data on renin and aldosterone levels after leptin treatment in vivo.1 Whereas renin levels were unchanged, aldosterone tended to decrease at higher doses. In accordance with these findings, previous studies have shown that infusion of leptin caused natriuresis and diuresis.3 The authors suggest that reduced plasma aldosterone levels may be due to reduced potassium intake associated with leptin-induced anorexia. We suggest that a more likely explanation is a direct effect of leptin on the adrenal cortex. We have previously …