Differences in nutrient blood flow of red and white skeletal muscle in the cat

Abstract

Nutrient blood flow of a red (soleus) and white (gastrocnemius) hindlimb muscle of cat were measured in chronically prepared unanesthetized animals by 8%b method and in anesthetized animals by the 85kt washout technique. Blood flow of soleus averaged 26.7 ml/lOOg/min. by 86Rb and 30.5 ml/100 g/min. by 85Kr. Flow of gastrocnemius was 9.8 ml/100 g/min. by 86Rb and 12.0 ml/100 g/min. by 85kt. Flow of soleus was about 3 times the flow of gastrocnemius. Simultaneous estimation of flow in other limb muscles by 86Rb showed that white limb muscle flow did not exceed 13 ml/100 g/min. and was one-third to one-sixth flow in red limb muscle. Flow in extraocular muscle was 91.5 ml/100/g min. and myocardium (left ventricle) was 144 ml/100 g/min. Blood flow to red skeletal muscle in cat limbs is greater than to white muscle and in general probably parallels the degree to which any muscle depends on aerobic metabolism rather than its speed of contraction.