Lactate and pyruvate metabolism in the exercising ischemic limb.

Abstract

External iliac vein blood flow was measured in 9 subjects with occlusive atterial disease of the lower limbs and 1 normal subject during and after exercise. The arteriovenous differences in lactate, pyruvate and O2 content were measured. Peak blood flow was lowest in those patients with severe proximal arterial disease, and was often delayed into the recovery period. Oxygen consumption and lactate production were similarly prolonged among these subjects. Total excess lactate accounted for a greater part of total lactate production in the patients with severe reduction of blood flow than in those with relatively high peak flows. There was a positive correlation between local O2 debt and excess lactate production. There was no evidence of lactic acid uptake by the limbs. Pyruvate release was slight and there was occasional evidence of pyruvate uptake by the limbs in the recovery period. The lactate pyruvate ratio in the arterial and venous blood was higher in pre-exercise period than at some stage of the recovery period.