Local blood flow is not linked to lactate within single rabbit skeletal muscles

A marked regional distribution in blood flow within single skeletal muscles on a non-microvascular level, i.e. at the level of large arterioles or small arteries, is present in dog, cat and rabbit. The mechanism for this perfusion pattern is not known. The goal of the present study was to see if regional blood flow was correlated to regional lactate metabolism. Anesthetized rabbits were studied. Blood flow to 0.25 g muscle samples was measured with microspheres whereas lactate content and lactate dehydrogenase activity were determined in extracts of these samples. No correlation was detected between regional blood flow and regional lactate or lactate dehydrogenase either at rest or during exercise hyperemia. Expressed as the coefficient of variation (CVc), regional blood flow showed a marked scatter, the CVc ranged from 0.32 to 0.35. The corresponding CVc for both lactate and lactate dehydrogenase activity ranged from 0.16 to 0.19. It is concluded that regional blood flow is not correlated to regional lactate metabolism. The regional distribution in blood flow was markedly more uneven than that for lactate content and for lactate dehydrogenase activity.