Functional heterogeneity of leucine pools in human skeletal muscle

Research was conducted to determine the isotopic enrichment of leucyl-tRNA in vasture lateralis muscle from human subjects and its comparison with other leucine pools. Quality control assay samples were analyzed to check the interassay variability for [13C]leucine measurements. Plasma insulin concentration increased after the ingestion of carbohydrate and mixed meals. Results indicated that the enrichment values of plasma alpha-ketoisocaproate (KIC), tissue fluid KIC and plasma leucine are different from muscle leucyl-tRNA.