Postnatal development of hepatic xanthine oxidase in baby pigs and turnover of purine catabolites at reduced ambient temperature. |
| |
Authors: | D Giesecke G Heiss W Erhardt R Rosskopf |
| |
Institution: | Institut für Physiologie, Physiologische Chemie und Ern?hrungsphysiologie, Universit?t München, Germany. |
| |
Abstract: | 1. The activity of xanthine oxidase in liver samples of baby pigs up to 4 weeks of age was investigated. On the 3rd day of life the turnover of hypoxanthine and of uric acid were measured after intravenous injection of 3H- and 14C-labelled tracers into animals kept at normal (32 degrees C) and reduced (20 degrees C) ambient temperature. 2. Hepatic xanthine oxidase activity increased progressively from 2 to 28 days of age (r = 0.689; P < 0.001). The increase of Vmax and of KM within 3-4 weeks was about 4.5-fold. 3. In 3-day-old baby pigs kept at normal temperature, pool size and turnover was about 10-fold higher for hypoxanthine than for uric acid. 4. At reduced ambient temperature, the pool size of uric acid increased 3.9-fold (P < 0.01) and turnover 1.6-fold (P < 0.05). For hypoxanthine the increases were insignificant. |
| |
Keywords: | |
|
|