Amino acid metabolism after lambda-carrageenan injury to rat skeletal muscle

To evaluate whether the alterations in amino acid (AA) metabolism that follow the lambda-carrageenan injury are direct consequences of wounding and are therefore independent of food intake, plasma AA, in vivo muscle intracellular free AA, and AA release during isolated hindlimb perfusions were determined in pentobarbital-anesthetized rats with lambda-carrageenan-induced hindlimb muscle wounds (W) and in pair-fed (PFC) and ad libitum-fed (ALC) non-wounded controls. Both PFC and W animals showed different plasma and muscle intracellular AA composition that ALC. The alterations observed in these compartments in W animals may not have resulted exclusively as a consequence of the wound. Wounded hindlimbs released more AA during perfusion than either control group. The marked increase in net protein catabolism of W muscle appeared to be related to wounding and not a consequence of partial starvation. The normalized release (amino acid/phenylalanine ratio) of glutamine (W less than ALC), alanine (W less than PFC and ALC), and the branched-chain amino acids (W greater than PFC and ALC) differed among groups, suggesting an alteration in the metabolism of these AA in W tissue.