Protein synthesis after experimental injury in pigs. A comparison of infusion solutions with different amino acid patterns.

This study compared the effect of three amino acid solutions on protein metabolism after injury by measuring plasma amino acid pattern, nitrogen balance, total body protein synthesis and utilisation of administered nitrogen in an experimental protocol using pigs. Protein synthesis and nitrogen utilisation were determined using a 15N-tracer technique with recourse to mathematical model concepts. Control animals which had not undergone surgery had a lower urinary nitrogen excretion, a more favourable nitrogen balance, greater total body protein synthesis and utilisation of the infused amino acids during the infusion of an amino acid solution with a standard pattern of amino acids (A) than the operated animals infused with either solution A or two other test amino acid solutions B and C. Comparison of the post-operative data showed that if solution A is compared with solution (B) whose amino acid content takes account of changes in plasma amino acids following trauma and a solution (C) which contains a high fraction of branched chain amino acids, solution (B) yields the best results in respect of total body protein synthesis and nitrogen utilisation.