Elucidation of roles of Na^+-driven cation transporter in blood pressure control and arterial lesions

点击翻译按钮获取中文摘要

Excessive salt intake is a major risk factor for hypertension Here we identify the role of Na^+/Ca^<2+> exchanger type 1 (NCX1) in salt-sensitive hypertension using SEA0400, a specific inhibitor for Ca^<2+> entry via NCX1, and genetically engineered mice. SEA0400 lowers arterial blood pressure in salt-dependent hypertensive rat models, but not in normotensive rats or other types of hypertensive rats. Infusion of SEA0400 into the femoral artery in salt-dependent hypertensive rats increases arterial blood flow indicating peripheral vasodilation. SEA0400 reverses ouabain-induced cytosolic Ca^<2+> elevation and vasoconstriction in arteries. Furthermore, heterozygous NCX1-deflcient mice have low salt-sensitivity, whereas transgenic mice that specifically express NCX1.3 in smooth muscle are hypersensitive to salt SEA0400 significantly lowers the blood pressure in salt-dependent hypertensive mice expressing NCX1.3, but not in SEA0400-insensitive NCX1.3 mutants. These findings indicate that salt-sensitive hypertension is triggered by Ca^<2+> entry via NCX1 in arterial smooth muscle and suggest that NCX1 inhibitors might be useful therapeutically.