Research note: beta-adrenergic agonist effects on liver and breast muscle protein synthesis in female chicks

The effect of administration of clenbuterol, a beta-adrenergic agonist, on live weight gain and protein synthesis of liver and breast muscle was investigated in 32 White Leghorn chicks. Protein synthesis was measured by injection of [3H]phenylalanine in a wing vein using the flooding dose method. No significant changes in body weight gain were caused by dietary administration of the beta-agonist at .25 mg/kg of diet from 3 to 6 wk of age, but fat retention in the liver and breast muscle was significantly reduced by the drug treatment. No stimulating effect on protein synthesis of the beta-agonist administration was found either in the breast muscle or in the liver. Protein synthesis in the breast muscle was unchanged whereas that in the liver was reduced significantly by feeding clenbuterol.