Determinant Role of the Severity of Hypoxia in the Induction of Reoxygenation Injury in Cat Lung. Hyun Jung Nam， Yoo Kyung Kim， Heung Sik Na， and Seung Kil Hong Department of Physiology， Korea University College of Medicine， Seoul 136 -705， Korea A1though reoxygenation is the best way to salvage hypoxic tissues， reduced oxygen species (ROS) generated during reoxygenation are known to cause further tissue injuries and the induction of heat shock proteins (HSPs). The present study was undertaken to determine any causal relatiOI빼ip between t址severity of hypoxia and the opposite outcomes， either beneficial or detrimental， of the subsequent reoxygenation by measuring the HSP72. To this aim， one group (6 male cats， 2.5