Defective l-Arginine–Nitric Oxide Pathway in Offspring of Essential Hypertensive Patients

Background Essential hypertension is characterized by impaired endothelium-dependent vasodilation. The present study was designed to investigate whether this abnormality is a primary defect or a consequence of blood pressure increases. Methods and Results In offspring of essential hypertensive patients (n=34) and normotensive subjects (n=30), we evaluated forearm blood flow (strain-gauge plethysmography) modifications induced by intrabrachial acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 μg·100 mL−1·min−1), an endothelium-dependent vasodilator, and sodium nitroprusside (1, 2, and 4 μg·100 mL−1·min−1), an endothelium-independent vasodilator. Minimal forearm vascular resistances also were calculated as the ratio between mean intra-arterial pressure and maximal forearm blood flow induced by forearm ischemia and hand exercise. Vasodilation to acetylcholine was significantly (P<.01) blunted in offspring of hypertensive patients compared with offspring of normotensive subjects, whereas the responses to sodium nit...