[Activity of pyruvate dehydrogenase in embryonic and postnatal chicken liver].

The activity of pyruvate dehydrogenase (EC 1.2.4.1) in chicken liver embryos remains constant up to the stage of hatching, and is increased by 50-70% during the first days of postnatal development and 6-7-fold on the ninth day. The enzyme activity in adult chickens is approximately equal to that in embryonic liver. The system of pyruvate dehydrogenase activation is labile; however, it may be stabilized by an addition of serum to embryonic liver homogenates. The amount of the inactive form of pyruvate dehydrogenase in embryonic liver makes up to approximately 50% of total activity. No stabilizing effect of the serum on the pyruvate dehydrogenase from young and adult chicken liver was observed.