目的 研究虫草素制剂对百草枯致大鼠肺纤维化的治疗作用。方法 90只健康雄性SD大鼠随机分为：对照组、模型组，地塞米松（阳性药，1 mg/kg）组，虫草素制剂低、中、高剂量（125、250、500 mg/kg）组，虫草活力素A（500 mg/kg）组，虫草活力素B（500 mg/kg）组。除对照组外，其余各组于实验第1天ip百草枯溶液17 mg/kg，1次染毒，并开始给药30 d，期间称量动物体质量，记录动物大体状况及死亡情况。给药结束，取肺观察动物肺脏大体情况，检测肺组织中羟脯氨酸（HYP）水平，并进行Masson染色观察肺纤维化病理变化。结果 虫草素制剂可改善肺纤维化大鼠状态，促进大鼠体质量恢复；虫草素制剂各个剂量组均能降低肺组织中HYP水平，其中高剂量组、虫草活力素A和B组与模型组比较差异显著（P<0.01）；地塞米松组和虫草素制剂高剂量组以及虫草活力素A、B组均不同程度的减少了纤维化组织，与模型组比较，纤维化程度较轻。结论 虫草素制剂能有效降低肺纤维化大鼠肺组织中HYP水平，改善肺的组织结构和纤维化病理变化。

Objective To study the therapeutic effect of cordycepin preparation on gramoxone-induced pulmonary fibrosis in rats. Methods Totally 90 Wistar rats were divided into eight groups: control group; model group; dexamethasone (positive drug, 1 mg/kg) group; cordycepin preparation low, medium, and high dose groups (125, 250, 500 mg/kg); Cordy Max A (500 mg/kg) group, and CordyMax B (500 mg/kg) group. Pulmonary fibrosis was induced by ip injection of gramoxone (17 mg/kg). Then the rats were treated for 30 d and the body weight, generan situation, and death of the animals were recored. After treatment, lung tissues were examined for hydroxyproline (HYP) levels and lung pathological changes. Results Cordycepin preparation could improve the status of the rats with pulmonary fibrosis induced by bleomycin; All the three doses of cordycepin preparation could reduce animal HYP content in lung tissue, the high dose group and CordyMax A or CordyMax B group compared with the model group were significantly different (P<0.01); Compared with model group, the degree of fibrosis of prednisone acetate group, cordycepin preparation high dose group, CordyMax A and CordyMax B group eased a little. Conclusion Cordycepin preparation can effectively reduce the HYP content in lung tissue of the rats with pulmonary fibrosis induced by gramoxone, improve the organization structure and the pathological changes of lung.