BAX and Hyperbilirubinemia: These changes are consistent with the ability of bilirubin to induce apoptosis observed in previous reports.30, 31 Furthermore, we observed in newborn rats that hyperbilirubinemia induced with intraperitoneal injections of bilirubin resulted in an increase in Ub-prs, concurrently with decreases of Nissl bodies and increases of Bax in the brain (Figure 6).