Protein Synthesis by Heart Muscle Ribosomes: An Effect of Insulin Independent of Substrate Transport

Abstract
Ribosomes from heart muscle of diabetic animals perfused for 15 minutes with insulin, but without added substrate, were more active in the catalysis of protein synthesis than were ribosomes from hearts perfused without insulin. This effect of insulin on the efficiency of protein synthesis seems not to result from transport of some critical substrate into muscle, nor is the effect on ribosomes mediated by a product of a tissue other than muscle.