Peripheral vascular tone in patients with cirrhosis: role of the renin-angiotensin and sympathetic nervous systems

Objective: The aims of the study were to establish the roles of angiotensin II and of the cardiopulmonary baroreceptor reflex in the regulation of peripheral vascular tone in patients with cirrhosis. Methods: Forearm blood flow responses to subsystemic, locally active intrabrachial infusions were measured in patients with Child's Grade C cirrhosis and matched controls using bilateral venous occlusion plethysmography. Responses were determined to the angiotensin II type I receptor antagonist, losartan, noradrenaline, angiotensin II and the nitric oxide synthase inhibitor, l- NG -monomethyl arginine. Results: Losartan at 30 and 90 μg/min caused no significant change in blood flow in controls, but caused 23±6% and 27±5% increases in patients respectively ( p