Study on Lung Injury of Rats Caused by Paraquat Poisoning

[Objective] To observe the lung injury of rats with once intragastric administration of paraquat.[Method] 20 rats were randomly divided into control group and paraquat group,rats in paraquat group were given 50mg/kg paraquat only once,while that in control group were given saline instead.Then the treadmill training of rats was observed before and after intragastric administration,the times of rats falling from the treadmill in the two groups before and 5,10,15 days after administration were compared.Rats were killed in the 15th days exposure to paraquat,their lung tissues were collected to measure their hydroxyproline content by alkaline hydrolysis and observe the pathological changes by HE staining.[Result] The general condition of rats was poor in paraquat group.Their average food intakes were significantly lower than that of the control group,the times of rats falling from treadmill in those two groups differed insignificantly before administration,but the falling times of paraquat group increased than the control group.The hydroxyproline content in lung tissues of paraquat rat was significantly higher than the control group,pathological section showed alveolar collapse,widened alveolar septum,and fibrous thickening of the interstitial in paraquat group.[Conclusion] One time paraquat exposure would lead to lung fibrosis in rats.