Cooperation Between Insulin and Leptin in the Modulation of Vascular Tone

Abstract

High levels of insulin and leptin have been reported in human hypertension, suggesting a role for these metabolic hormones in blood pressure homeostasis. These hormones interact on intermediate metabolism, but nothing is known about their interaction at the vascular level. Our data demonstrate that insulin (0.6 nmol/L) is able to enhance vasodilation induced by leptin (10 ⁻¹¹ to 10 ⁻⁶ mol/L; percentage change in maximal vasodilation, 39±3% vs 26±2%; n=6, P 473 and Thr ³⁰⁸ and of endothelial NO synthase in Ser ¹¹⁷⁷ . In conclusion, our data demonstrate that insulin and leptin cooperate in the modulation of vascular tone through enhancement of endothelial NO release. This phenomenon could have a major impact on the regulation of the cardiovascular system, principally in those clinical conditions characterized by endothelial NO dysfunction and metabolic disorders, such as arterial hypertension.