[Synthesis of proteins in heart mitochondria during postnatal development of the rat]

Proteins of inner mitochondrial membranes of the albino rat myocardium during postnatal development of 1, 3 and 6 months old animals were electrophoretically separated in 10% polyacrylamide gel. The rate of 14C-amino acids incorporation into examined proteins was determined in vitro. Specific radioactivity of the total mitochondrial fraction decreased in the course of the postnatal development. That of outer membranes remained unchanged, though it sharply increased in inner membranes of mature animals as compared with animals aged one month. Levels of radioactive precursor incorporation in separate protein fractions of inner membranes of the myocardium mitochondria were estimated.