中文摘要：

目的探讨中药穿心莲内酯对大鼠放射性损伤的防护作用。方法将60只雄性SD大鼠随机分为健康对照组、模型组和中药组。中药组大鼠定期进行穿心莲内酯溶液（分为2个剂量组）灌胃，模型组大鼠给予生理盐水灌胃，健康对照组大鼠正常饮水。10d后给予^60Coγ射线一次性全身均匀照射，1、2和4Gy。继续饲养1d后，处死全部动物，取其肝脏，立即用4％多聚甲醛固定，常规制作石蜡切片，采用HE染色检测肝组织细胞形态学变化，TUNEL法染色检测不同组细胞凋亡情况。结果健康对照组和模型组大鼠肝脏HE染色显示病变相似，随辐射剂量的增大，肝细胞水肿、肝窦扩张充血、炎性反应等组织损伤程度加重；TUNEL法检测肝细胞凋亡率无明显差别。同等剂量下，中药组大鼠HE染色病变较对照组和模型组轻，且肝细胞凋亡率显著降低（t=2．19-4.80，P〈0.05）。结论穿心莲内酯对辐射损伤有一定的防护作用。

英文摘要：

Objective To explore the effects of andrographolide （AP）, extracted from the traditional Chinese herb Andrographlis paniculata （AP） , on injury induced by radiation exposure. Methods Sixty male rats were randomly divided into 4 equal groups and irradiated with ^60Co γ-rays at the doses of 1,2, and 4 Gy, respectively： low dose AP group （intragastrically administered with AP at the dose of 100 mg/kg daily for 10 d before irradiation） , and high dose AP group （intragastrically administered with AP at the dose of 200 mg/kg daily for l0 d before irradiation）, model group （administered with the same volume of normal saline instead of AP for 10 d before irradiation） , and control group （irradiated only at 3 different doses）. One day after irradiation all rats were killed with their livers being fixed to make paraffin section. The morphological feature was observed under light microscope after HE staining, and the cell apoptosis was detected by TUNEL technology. Results Compared to the control and model groups, the pathological changes of liver were significantly gentler in the AP treatment groups. The apoptosis rates of the liver cells of all the AP sub-groups were significantly lower than those of the control and model subgroup （t =2.19-4.80, P 〈 0.05）. Conclusions AP might have prevention effect against radiation exposure.