Effects of inhaled hydrogen sulfide on smoke inhalation-induced acute lung injury in rats

The study aimed to observe the effects of inhaled hydrogen sulfide on smoke inhalation-induced acute lung injury in an animal model. In this study, male Sprague-Dawley (SD) rats were divided into intervention and control groups. The intervention group was divided into three subgroups: smoke group (n=6), smoke+H2S 3 h group (n=6), and smoke+H2S 6 h group (n=6). A control group (n=6) received treatment with fresh air only. After exposure to treatment conditions and blood gas analysis, intervention and control group rats were sacrificed and pathological changes in pulmonary tissue were observed under a light microscope. Enzyme-linked immunosorbent assay (ELISA) was used to analyze the levels of malondialdehyde (MDA), inducible nitric oxide synthase (iNOS), and the p65 subunit of nuclear factor kappaB (NF-κBp65) in homogenized lung tissue. The expression of iNOS mRNA in homogenized lung tissue was analyzed using fluorescence quantitative polymerase chain reaction (PCR). In the smoke+H2S 3 h and smoke+H2S 6 h groups, the sum integrated optical density of NF-kBp65 and MDA, the relative expression of iNOS mRNA, and the concentrations of NF-kBp65, iNOS, and nitrogen monoxide (NO) in lung tissue decreased significantly compared to the smoke-only group. No significant differences in lung tissue pathology, blood oxygen analysis, lung wet-dry weight ratio, MDA level, and other indicators were present between the smoke+H2S 3 h group and smoke+H2S 6 h group. Inhaled hydrogen sulfide shows a significant protective effect on cotton smoke inhalation-induced pulmonary injury, and it can ameliorate oxidative stress and tissue inflammation.