Resistance of isolated pulmonary mitochondria during in vitro anoxia/reoxygenation

The aim of the study was to investigate the effect of in vitro anoxia/reoxy genation on the oxidative phosphorylation of isolated lung mitochondria. Mi tochondria were isolated after harvesting from fresh pig lungs flushed with Euro-Collins solution. Mitochondrial respiratory parameters were determine d in isolated mitochondria before anoxia (control), after 5-45 min anoxia f ollowed by 5 min reoxygenation, and after 25 or 40 min of in vitro incubati on in order to follow the in vitro aging of mitochondria during respiratory assays. Respiratory parameters measured after anoxia/reoxygenation did not show any oxidative phosphorylation dysfunction, indicating a high resistan ce of pulmonary mitochondria to in vitro anoxia/ reoxygenation (up to 45 mi n anoxia). These results indicate that mitochondria are not directly respon sible of their oxidative phosphorylation damage observed after in vivo isch emia (K. Willet et al., Transplantation 69 (2000) 582) but are a target of others cellular injuries leading to mitochondrial dysfunction in vivo. (C) 2000 Elsevier Science B.V. All rights reserved.