ObjectiveTo investigate the expression of C/EBP homologous protein (CHOP) in lung tissue of chronic intermittent hypoxia rats, and explore the intervention effect of edaravone and its possible mechanism.MethodsA total of 120 adult male Wistar rats were randomly divided into three groups: a normal control group (UC group), a chronic intermittent hypoxia group (CIH group), an edaravone intervention group (NE group), and a normal saline group (NS group). The above four groups were also randomly divided into five time subgroups of 3 days, 7 days, 14 days, 21 days and 28 days, respectively, with 6 rats in each time subgroup. The histopathological changes of lung tissue were observed by hematoxylin-eosin (HE) staining and the expression of CHOP in lung tissue was detected by immunohistochemical method.ResultsHE staining results showed that there was no obvious pathological change in UC group. The epithelial cells of lung tissue in CIH group showed edema, hyperemia, widening of alveolar septum and inflammatory cell infiltration. The pathological injury was more serious with the prolongation of intermittent hypoxia time. There were also pathological changes in NE group, but the degree of lung tissue injury was significantly lower than that in CIH group. The results of immunohistochemistry showed that the expression of CHOP in CIH group was significantly higher than that in UC group. The expression of CHOP in NE group was higher than that in UC group, but it was still significantly lower than that in CIH group.ConclusionsThe expression of CHOP protein in lung tissue of chronic intermittent hypoxic rats is enhanced and the high expression of CHOP protein plays a certain role in the lung injury of chronic intermittent hypoxia rats complicated with lung injury. Edaravone may protect lung tissue from chronic intermittent hypoxia by inhibiting the expression of CHOP.