目的 探究龙血通络胶囊对异丙肾上腺素（isoproterenol，ISO）诱导大鼠心肌缺血的保护作用。方法 Wistar大鼠随机分为对照组、模型组、地奥心血康（62.50 mg/kg）组和龙血通络胶囊低、中、高剂量（103.12、206.25、412.50 mg/kg）组，每组10只。各组连续28 d ig给予相应药物，第27、28天给药1 h后，除对照组sc生理盐水外，其余各组sc ISO（150 mg/kg）。第1次sc ISO 48 h后摘取大鼠心脏，计算心脏指数；采用苏木素-伊红（HE）染色观察各组大鼠心肌组织病理变化；采用ELISA法检测各组大鼠血清中肌酸激酶（creatine kinase，CK）、肌酸激酶同工酶（creatine kinase-MB，CK-MB）和心肌钙蛋白-I（cardiac troponin-I，cTn-I）水平；采用试剂盒检测大鼠血清中乳酸脱氢酶（lactate dehydrogenase，LDH）、超氧化物歧化酶（superoxide dismutase，SOD）和天冬氨酸氨基转移酶（aspartate aminotransferase，AST）活性以及丙二醛（malondialdehyde，MDA）水平；采用TUNEL染色观察大鼠心肌细胞凋亡情况；采用免疫组化法检测心肌组织中核因子E2相关因子2（nuclear factor-erythroid 2-related factor 2，Nrf2）、血红素加氧酶-1（hemeoxygenase-1，HO-1）和剪切型半胱氨酸天冬氨酸蛋白酶-3（cleaved cystein-asparate protease-3，cleaved Caspase-3）蛋白表达。结果 与对照组比较，模型组大鼠心脏指数显著升高（P<0.001），血清中cTn-I、CK-MB、CK、MDA水平以及LDH、AST活性显著升高（P<0.001），SOD活性降低（P<0.001），心肌组织出现明显的病理变化（P<0.001），心肌细胞凋亡率显著升高（P<0.001），心肌组织中cleaved Caspase-3、Nrf2和HO-1蛋白表达水平均显著升高（P<0.05、0.001）。与模型组比较，龙血通络胶囊组大鼠心脏指数明显降低（P<0.001），血清中cTn-I、CK-MB、CK、MDA水平以及LDH、AST活性显著降低（P<0.05、0.01、0.001），SOD活性显著升高（P<0.001）；心肌组织的病理性改变得到改善（P<0.05）；心肌组织中心肌细胞凋亡率显著降低（P<0.01）；心肌组织中cleaved Caspase-3蛋白表达显著降低（P<0.05、0.01），Nrf2、HO-1蛋白表达显著升高（P<0.01、0.001）。结论 龙血通络胶囊可改善ISO诱导大鼠心肌缺血损伤，其作用机制可能是通过调节Nrf2/HO-1通路，进而抑制氧化应激诱导的细胞凋亡。

Objective To investigate the protective effect of Longxuetongluo Capsule (龙血通络胶囊) on isoproterenol (ISO)-induced myocardial ischemia in rats. Methods Wistar rats were randomly divided into control group, model group, Di'ao Xinxuekang (62.50 mg/kg) group and Longxuetongluo Capsule low-, medium- and high-dose (103.12, 206.25, 412.50 mg/kg) groups, with 10 rats in each group. Each group was ig corresponding medication for 28 consecutive days. After 1 h of administration on 27th and 28th days, except for the control group with physiological saline, all other groups were sc ISO (150 mg/kg). The hearts of rats were collected and heart weight index was calculated 48 h after the first subcutaneous injection of ISO; Hematoxylin-eosin (HE) staining was used to observe the pathological changes of myocardial tissues in each group; The levels of creatine kinase (CK), creatine kinase-MB (CK-MB), cardiac troponin-I (cTn-I) were detected by ELISA; The activities of lactate dehydrogenase (LDH), superoxide dismutase (SOD) and aspartate aminotransferase (AST) and level of malondialdehyde (MDA) in serum were detected by kit; TUNEL staining was used to observe the apoptosis of cardiomyocytes in rats; The expressions of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and cleaved cystein-asparate protease-3 (cleaved Caspase-3) in myocardial tissue were detected by immunohistochemistry. Results Compared with control group, heart weight index of rats in model group was significantly increased (P < 0.001), levels of cTn-I, CK-MB, CK, MDA and activities of LDH, AST in serum were significantly increased (P < 0.001), SOD activity in serum was decreased (P < 0.001); Obvious pathological changes were observed in myocardial tissue (P < 0.001), cardiomyocyte apoptosis rate was increased (P < 0.001); The expressions of cleaved Caspase-3, Nrf2 and HO-1 proteins in myocardial tissue were up-regulated (P < 0.05, 0.001). Compared with model group, heart weight index of rats in Longxuetongluo Capsule group was significantly decreased (P < 0.001), levels of cTn-I, CK-MB, CK, MDA and activities of LDH, AST in serum were significantly decreased (P < 0.05, 0.01, 0.001), SOD activity was significantly increased (P < 0.001); The pathological changes of myocardial tissue were ameliorated (P < 0.05); The cardiomyocyte apoptosis rate in myocardial tissue was significantly decreased (P < 0.01); The expression of cleaved Caspase-3 in myocardial tissue was significantly decreased (P < 0.05, 0.01), the expressions of Nrf2 and HO-1 in myocardial tissue were significantly increased (P < 0.01, 0.001). Conclusion Longxuetongluo Capsule can ameliorate ISO-induced myocardial ischemia injury in rats, and its mechanism may be related to the regulation of Nrf2/HO-1 pathway, thereby inhibiting oxidative stress-induced apoptosis.

R285.5

2021年国家中医药管理局岐黄学者项目（国中医药人教函[2022]6号）