Amino acid infusion increases the sensitivity of muscle protein synthesis in vivo to insulin. Effect of branched-chain amino acids

Biochem J. 1988 Sep 1;254(2):579-84. doi: 10.1042/bj2540579.


Rates of muscle protein synthesis were measured in vivo in tissues of post-absorptive young rats that were given intravenous infusions of various combinations of insulin and amino acids. In the absence of amino acid infusion, there was a steady rise in muscle protein synthesis with plasma insulin concentration up to 158 mu units/ml, but when a complete amino acids mixtures was included maximal rates were obtained at 20 mu units/ml. The effect of the complete mixture could be reproduced by a mixture of essential amino acids or of branched-chain amino acids, but not by a non-essential mixture, alanine, methionine or glutamine. It is concluded that amino acids, particularly the branched-chain ones, increase the sensitivity of muscle protein synthesis to insulin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / blood
  • Amino Acids / pharmacology*
  • Animals
  • Glucose / pharmacology
  • Infusions, Intravenous
  • Insulin / pharmacology*
  • Male
  • Muscle Proteins / biosynthesis*
  • Rats
  • Rats, Inbred Strains


  • Amino Acids
  • Insulin
  • Muscle Proteins
  • Glucose