The effects of hypoxanthine, xanthine oxidase and hyperoxia on the accumulation of bilirubin and albumin in young rat brain

• Published in: Early human development Vol. 30; no. 2; pp. 171 - 177
• Main Authors: Hansen, Thor Willy Ruud, Poulsen, Jan Peter, Bratlid, Dag
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier Ireland Ltd 01.09.1992; New York,NY Elsevier; Amsterdam
• Subjects: albumin; Albumins - metabolism; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; bilirubin; Bilirubin - metabolism; bilirubin encephalopathy; Biological and medical sciences; brain; Brain - metabolism; Emergency and intensive care: neonates and children. Prematurity. Sudden death; Free Radicals; hyperoxia; Hypoxanthine; Hypoxanthines - physiology; Intensive care medicine; Male; Medical sciences; Oxygen - metabolism; Oxygen - poisoning; rat; Rats; Rats, Sprague-Dawley; xanthine oxidase; Xanthine Oxidase - physiology; free radicals; hyperoxia; hypoxanthine; rat; bilirubin encephalopathy; albumin; bilirubin; brain; xanthine oxidase; Nervous system diseases; Pathophysiology; Rat; Rodentia; Bilirubin; Free radical; Vertebrata; Experimental disease; Mammalia; Newborn animal; Animal; Encephalopathy; Hypoxanthine; Brain (vertebrata)
• ISSN: 0378-3782; 1872-6232
• DOI: 10.1016/0378-3782(92)90144-6

Hyperoxia has been suggested as a risk factor for kernicterus. The toxicity of hyperoxia may be mediated by free radicals. We investigated the effects of free radicals, formed by the hypoxanthine/xanthine oxidase system, with and without additional hyperoxia, on the accumulation of bilirubin and albumin in rat brain. Hypoxanthine was infused for 60 min into retrograde carotid catheters in awake, young, male SPRD rats. After 30 min the infusion was briefly interrupted to inject xanthine oxidase 1 U/kg through the same catheter. Group I (controls) received 0.9% NaCl in lieu of hypoxantine/xanthine oxidase. Groups I and II breathed room air at all times, while group III breathed 90% O 2. After 60 min all groups received a bolus dose of 125I-albumin through a peripheral venous catheter, followed by bilirubin 25 mg/kg for 5 min, then bilirubin 35 mg/kg for 55 min. There were no significant differences between the groups as regards serum bilirubin, serum albumin, brain bilirubin, or brain albumin. Neither during normoxic nor hyperoxic conditions did the hypoxanthine/xanthine oxidase system increase the accumulation of bilirubin or albumin in rat brain.