Effect of insulin on protein catabolism after injury in young animals

Injury is followed by a negative nitrogen balance, muscle protein breakdown and loss of body mass. The intensity of these changes correlates with trauma severity. Reversion of the catabolic state has long been attempted. Recently, it has been shown that the use of insulin might inhibit protein catabolism after severe trauma. The present study was undertaken to assess the effect of insulin on post-injury catabolism in young rabbits submitted to parenteral nutrition. Concomitantly, changes in liver and skeletal muscle nitrogen contents were also studied to elucidate the mechanism of insulin's anabolic effect after trauma. We found that only in catabolic states did insulin produce a significant nitrogen-sparing effect, probably due to the capacity of the hormone to inhibit muscle proteolysis.