A simple and controllable method for reproduction of a model of high oxygen tension induced acute lung injury

To explore a simpler, more economic and reproducible method to reproduce a model of high oxygen induced acute lung injury (HALI) in rats.An animal feeding box equipped with a controllable high oxygen was designed. 100 Sprague-Dawley (SD) rats were divided into normal control group and HALI group by random number table method, with 50 rats in each group. Each group was randomly subdivided into five subgroups according to the duration of exposure to high oxygen, namely 0, 24, 48, 72 and 96-hour subgroups, with 10 rats in each subgroup. The rats in normal control group were kept in cages with ambient air, and the rats in HALI group were kept in an oxygen tank in which the oxygen concentration was higher than 90% volume ratio, with the temperature maintained at 25-27?centigrade, humidity of 50%-70%, and CO2 concentration 0.05). There were significant differences in changes between 24, 48, 72, and 96 hours as compared with those of the normal control group: OI (mmHg): 24 h 306.19±37.23 vs. 435.65±25.34 and 96 h 245.58±35.25 vs. 465.42±24.75; RI: 24 h 0.31±0.06 vs. 0.24±0.04 and 96 h 0.44±0.03 vs. 0.24±0.06. The same as true in pathological scores of lung tissue: 24 h 0.90±0.74 vs. 0.00±0.00 and 96 h 4.80±1.23 vs. 0.00±0.00; lung W/D ratio: 24 h 4.14±0.46 vs. 3.79±0.44 and 96 h 5.18±0.25 vs. 4.12±0.91, all P < 0.05.A self-designed high oxygen box is simple, easy to operate and reproduction of HALI model can be attained. Sustained exposure to high concentrations of oxygen (≥ 90%) for 24 hours can replicate the HALI model successfully, and the most serious injury appears at 48-72 hours after exposure.