目的　观察双氢青蒿素对卡氏肺孢子虫超微结构的影响。方法　以醋酸可的松皮下注射 Wistar大鼠 6周 ,诱导建立肺孢子虫肺炎动物模型 ,用双氢青蒿素治疗大鼠 ,并用电镜观察大鼠肺切片中肺孢子虫超微结构。结果　双氢青蒿素可使肺孢子虫滋养体胞浆及包囊内出现空泡 ,线粒体肿胀、核膜破裂、内质网肿胀 ,囊内小体溶解破坏等超微结构改变。结论　双氢青蒿素主要对卡氏肺孢子虫膜系结构产生破坏作用 Objective To observe the effects of dihydroartemisinin on the ultrastructure of Pneumocystis carinii. Methods Wistar rats were injected subcutaneously with cortisone acetate for 6 weeks. The animal model of Pneumocystis pneumonia was induced and induced by dihydroartemisinin. The ultrastructure of Pneumocystis was observed by electron microscope. Results Dihydroartemisinin could induce ultrastructure changes such as vacuoles, mitochondria swelling, rupture of nuclear membrane, swelling of endoplasmic reticulum and dissolution and destruction of vesicles in trophozoites of P. pneumoniae. CONCLUSIONS: Dihydroartemisinin has a damaging effect on the membrane structure of Pneumocystis carinii