Tyrosine Phosphorylation of Apoptotic Proteins During Hyperoxia in Mitochondria of the Cerebral Cortex of Newborn Piglets

The present study tests the hypothesis that hyperoxia results in increased tyrosine phosphorylation of apoptotic proteins Bcl-2, Bcl-xl, Bax & Bad in the mitochondrial fraction of the cerebral cortex of newborn piglets. Twelve newborn piglets were divided into normoxic [Nx, n = 6], exposed to a FiO 2 of 0.21 for 1 h and hyperoxic [Hyx, n = 6], exposed to FiO 2 of 1.0 for 1 h. PaO 2 in Hyx group was maintained at 400 mmHg while the Nx group was kept at 80 to100 mmHg. The density (O.D.x mm 2 ) of phosphorylated Bcl2 protein on westernblot was 19.3 ± 3.6 in Nx and 41.5 ± 18.3 in Hyx, ( P