Antioxidant consumption during exercise in intermittent claudication.

Twenty male claudicant patients and nine age-matched controls were exercised on a treadmill. Blood and urine samples were taken before and after exercise. Total antioxidant concentration was measured using an enhanced chemiluminescent assay and microalbuminuria determined by radioimmunoassay. Claudicants had increased microalbuminuria after exercise. Mean (s.e.m.) antioxidant concentrations were similar for patients and controls at rest: 479(28) and 438(23) mumol/l respectively. Claudicants showed a significant decrease in antioxidant concentration 1 min after exercise to 428(27) mumol/l; this returned to 470(30) mumol/l by 10 min. A correlation was found between the decrease in antioxidant concentration and the increase in microalbuminuria (rs = -0.496, P < 0.05). This study supports the concept of ischaemia-reperfusion injury in claudicant patients and has implications for treatment.