A feature of lung injury associated with bronchopulmonary dysplasia in premature infants is the relative sensitivity of lung endothelial cells to injury. Although lung epithelial cells are more directly exposed to elevated oxygen levels, lung endothelial cells are the first site of injury. We have developed a cell culture model of this pattern of injury using rat aortic endothelial cells and rat lung epithelial cells. The cells were grown to confluence on fibronectin coated plates and treated with 95% oxygen for up to 96 h. Cell survival was quantified by determining mitochodrial dehydrogenase activity and normalized to air-treated controls. Confluent monolayers of each cell type were also treated with increasing doses of 4-hydroxy-2-nonenal(4HNE) for 3 h and cell survival determined. The data(Table 1) indicate that the endothelial cells are more susceptible than the epithelial cells to both 95% oxygen- and 4HNE-induced cytotoxicity and support a role for 4HNE in oxidative tissue injury.

Table 1
Full size table

(Supported by NIH HL42057).