[Study on lung injury induced by subchronic exposure to crotonaldehyde in male rats]

Objective: To observe the lung injury of male rats induced by sub-chronic exposure to crotonaldehyde, and to explore the possible mechanism of injury. Methods: Forty SPF male Wistar rats were randomly divided into control group and 3 groups in each group, and each group received 0.0, 2.5, 4.5, 8.5 mg/kg body weight crotonaldehyde solution for continuous intragastric administration. 120 d, once a day. After the end of the exposure, the body weight of the rats was measured, and the lung tissues were quickly separated after cervical dislocation. The organ coefficients were calculated and histopathological examination was performed to determine malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione. Peroxidase (GSH-Px) content; ELISA was used to measure interleukin (IL) -6, IL-1β, and tumor necrosis factor (TNF) -α in lung tissues. Results: Compared with the control group, the weight gain of the rats in the 4.5 and 8.5 mg/kg exposure groups was small, and the lung weight and organ coefficient of the exposed group decreased, the difference was statistically significant (P<0.05). In the exposed group, the lung tissue structure was disordered, the alveolar wall was thickened, and inflammatory cell infiltration was observed. Compared with the control group, the MDA activity in the serum of the rats in the 4.5 mg/kg and 8.5 mg/kg groups increased, and the SOD and GSH-Px activities decreased, the difference was statistically significant (P<0.05). TNF-α levels in the lung tissues of rats exposed to 4.5 mg/kg and 8.5 mg/kg, and levels of (IL) -6 and IL-1β in the lungs of rats in the 2.5, 4.5, and 8.5 mg/kg groups. Significantly increased, the difference was statistically significant (P<0.05) . Conclusion: Crotonaldehyde may induce inflammatory and oxidative stress damage in rats by up-regulating the expression of inflammatory factors in lung tissue and changing the oxidative balance.