Experimental study on therapeutic efficacy of tetrandrine on lung injury induced by acute of paraquat poisoning

Objective To investigate the antagonistic efficacy of tetrandrine (TET) on lung injury induced by acute paraquat poisoning. Methods Male Wistar rats were randomly divided into three groups(control group, non-treatment group and treatment group). The tetrandrine of 30 mg/kg was given by gastrogavage six hours after 32 rats were intraperitoneally injected with paraquat 15mg/kg (treatment group). Then the same dose of tetrandrine was given once a day. Normal saline of the same volume was given by gastrogavage in another 32 rats intraperitoneally injected with paraquat 15 mg/kg (non-treatment group). Seven rats were intraperitoneally injected by normal saline as the control group. Levels of maleie dialdehyde (MDA), activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in plasma and the lung homogenate of three groups were determined at 3 d,7 d, 14 d and 21 d after exposure to paraquat. Histological changes of the lungs were observed. Results The levels of M DA at 3 d both in plasma [(3.65±0.44)nmol/ml] and the tung homogenate [(9.54±0.92 )nmol/mg pro] of the non-treatment group significantly increased compared with the control group (P 0.05). The SOD activities of treatment group on the third day was significantly increased compared with the non-treatment group(P 0.05). The integral score of pulmonary fibrosis in the treatment group were significantly lower than in the non-treatment group(P<0.01). Conclusion TET has antagonistic effect against acute toxieity of paraquat through significant reduction of pulmonary fibrosis. Key words: Tetrandrine;  Paraquat;  Malon dialdehyde;  Glutathione peroxidase