Short-term Oral Administration of l-Arginine Improves Hemodynamics and Exercise Capacity in Patients with Precapillary Pulmonary Hypertension

Abstract

We sought to assess the effects of oral supplementation of L-arginine, the precursor of nitric oxide (NO), on hemodynamics and exercise capacity in patients with pulmonary hypertension. Acute hemodynamic responses to oral L-arginine (0.5 g/10 kg body weight) or placebo were examined in 19 patients with primary or precapillary secondary pulmonary hypertension. Cardiopulmonary exercise tests were performed to measure peak oxygen consumption (peak V O(2)) and the ventilatory response to carbon dioxide production (V E-V CO(2) slope) before and 1 wk after treatment with L-arginine (1.5 g/10 kg body weight/d) or placebo. Oral supplementation of L-arginine significantly increased plasma L-citrulline, which indicated enhancement of NO production. Supplemental L-arginine produced a 9% decrease in mean pulmonary arterial pressure (53 +/- 4 to 48 +/- 4 mm Hg, p < 0.05) and a 16% decrease in pulmonary vascular resistance (14.8 +/- 1.5 to 12.4 +/- 1.4 Wood units, p < 0.05). L-arginine modestly decreased mean systemic arterial pressure (92 +/- 4 to 87 +/- 3 mm Hg, p < 0.05). A 1-wk supplementation of L-arginine resulted in a slight increase in peak V O(2) (831 +/- 88 to 896 +/- 92 ml/min, p < 0.05) and a significant decrease in the V E- V CO(2) slope (43 +/- 4 to 37 +/- 3, p < 0.05) without significant systemic hypotension. Hemodynamics and exercise capacity remained unchanged during placebo administration. These results suggest that oral supplementation of L-arginine may have beneficial effects on hemodynamics and exercise capacity in patients with precapillary pulmonary hypertension.

Low-dose l -arginine administration increases microperfusion of hindlimb muscle without affecting blood pressure in rats

“…Although a great deal of research has been conducted on the effects of exogenous L-arginine on the circulatory system, most of the studies have focused on the effect of L-arginine administration on blood pressure in experimental models of hypertension (20)(21)(22) and in patients (16,23,24); the improvement of blood flow or exercise capacity in patients with chronic heart failure (17), hypertension (18), and hypercholesterolemia (25); and the prevention of atherosclerosis (11). Few reports exist on the effect of L-arginine on capillary blood flow in normotensive subjects (16,(26)(27)(28)(29).…”

“…Therefore, many investigators have been interested in the effects of supplementation with L-arginine to produce increased beneficial effects of NO, including prevention of the progression of atherosclerosis (11,12), prevention of pulmonary artery endothelial dysfunction (13,14), enhancement of cellular immune response of T lymphocytes (4), and amelioration of hypertension (15,16). Other studies indicate that oral supplementation of L-arginine also corrects endothelial dysfunction of chronic heart failure (17), and it increases exercise capacity in patients with precapillary pulmonary hypertension by increasing peak oxygen consumption and decreasing pulmonary arterial pressure and pulmonary vascular resistance thorough the action of NO (18).…”

Effects of Oral Supplementation of L-Arginine in the Treatment of Pulmonary Hypertension Secondary to Pulmonary Embolism: A Case Report

“…Nagaya et al have reported beneficial effects of short -term oral administration of L -arginine on hemodynamics and exercise capacity in patients with precapillary pulmonary hypertension in a randomized placebo -controlled study. Seven pulmonary hypertension secondary to pulmonary embolism patients were included in the examination 10) . Pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension share features of pulmonary remodeling, and the two disorders might be associated with pulmonary endothelial dysfunction 6) .…”

L-Arginine Levels among Hypertensive Patients in Sokoto, North Western Nigeria

“…L-arginine is an amino acid that is necessary for the body to make protein and is found in red meat, poultry, fish, and dairy foods. L-arginine has been shown to reduce pulmonary vascular resistance in humans with hypertension [28] …”