Increased endogenous nitric oxide production induced by physical exercise in peripheral arterial occlusive disease patients

The effects of 14-day physical exercise or iloprost treatment (0.5-2 ng/Kg/ min) on endogenous nitric oxide production and neutrophil adhesion were eva luated in 20 patients with peripheral arterial occlusive disease (Fontaine Stage II). Peripheral venous blood samples and 4-h urine samples were colle cted before, immediately after 14 days of therapy and 7-10 days after thera py in order to evaluate neutrophil adhesion, nitrite/nitrate and cGMP excre tion rates. A longer pain free walking distance was observed after exercise , compared to iloprost (>500 m in 3/10 subjects). Urinary nitrite/nitrate, as well as cGMP concentrations, significantly increased after exercise. Nit rite/nitrate excretion rate inversely correlated to neutrophil adhesion. No variations were observed in these parameters in iloprost treated patients. The improvement in claudication and the transient increase in urinary nitr ite/nitrate suggest a possible nitric oxide-dependent mechanism for the cli nical efficacy of physical exercise. The results from the present and previ ous observations indicate that, besides pharmacological treatments, a regul ar aerobic exercise improves peripheral arterial occlusive disease.