付伊萌，陈  茜，吴  帆，付梦婷

（１湖北中医药大学/针灸治未病湖北省协同创新中心，武汉  430061）

摘要：目的：观察电针预处理对慢性心肌缺血大鼠血管内皮生长因子(vascular endothelial growth factor，VEGF)的影响，探讨电针预处理防治慢性心肌缺血的作用机制。方法：采用 SPF 级雄性 wistar 大鼠 45 只，随机分为 3 组：正常组、模型组、电针预处理组，每组 15 只。除正常组连续 14 天皮下注射 0.9%NaCl 外(2mg/kd/d)，其他两组均每日给予异丙肾上腺素（Isoprenaline，ISO）（2mg/kg/d）皮下注射，每日一次，连续 14 天。 电针预处理组在当天造模前即给予针刺“内关”、 “关元”、 “足三里”， 该组同侧穴位组成一对，即同侧“内关”穴连接同侧“足三里”穴，连接 HAN-200 型电针仪，频率2Hz，电压 1.6V，强度 1mA，以大鼠肢体有震颤感为适宜强度，每次 10min，正常组和模型组相同时间抓取固定，每日一次，共 21 天。应用Agilent Sonos 5500 型彩色超声心动图诊断仪检测计算左室舒张末内径（LVEDD）、 左室收缩末内径（LVESD）以及左室射血分数（LVEF），以  LVEF≤45%为造模成功；记录治疗后各组大鼠的心电图及 ST 段电压变化；采用 Elisa 检测各组大鼠血清中的 VEGF 含量; Western  blotting 检测心肌梗死区 VEGF 表达。结果：模型组大鼠的左室舒张末期内径(LVEDD)、左室收缩末期内径(LVESD)均高于正常组（P＜0.01），左室射血分数（EF）低于正常组大鼠（P＜0.01）；电针预处理组 LVEDD 值低于模型组（P＜0.01），LVESD 值低于模型组（P＜0.01），EF 值高于模型组（P＜0.01）；造模后，模型组大鼠 ST 段电压明显高于正常组，血清中 VEGF 含量高于正常组（P<0.01）；造模及治疗后，电针预处理组大鼠的 ST 段电压低于模型组，电针预处理组 VEGF含量高于模型组（P<0.01）。模型组心肌组织梗死区 VEGF 蛋白表达低于正常组（P<0.01），电针预处理组心肌组织梗死区 VEGF 蛋白表达高于模型组（P<0.01）。结论：电针“内关”、“足三里”、“关元”预处理，可促进慢性心肌缺血大鼠 VEGF 表达，促进血管再生，改善心功能、缩小缺血心肌面积，有效防治慢性心肌缺血。 

关键词：电针预处理；心肌缺血；VEGF   

Abstract：Objective：To observe the effect of electroacupuncture preconditioning on vascular endothelial growth factor (VEGF) in rats with chronic myocardial ischemia, and to explore the mechanism ofelectro acupuncture preconditioning in preventing and treating chronic myocardial ischemia.   Methods：The 45  male  Wistar  rats  were  randomly  divided  into  3  groups:  control group,  model  group,  EA  group,  15  rats  in  each  group.In  addition  to  the  normal  group  for  14 consecutive  days  under  the  subcutaneous  injection  of  0.9%NaCl  (2mg/kd/d),  the  other  two groups  were  given  daily  ISO  (2mg/kg/d)  (ISO)  subcutaneous  injection,  once  a  day,  for  14 consecutive  days.The  EA  group  began  to  give  acupuncture  treatment  before  the  start  of that, which   is given needling  "Neiguan","Guanyuan" and "Zusanli",connected the same side of "Neiguan" with "Zusanli", connecting the HAN-200 electro acupuncture device, frequency 2Hz, voltage 1.6V, intensity 1mA,which is suitable for the rat limb tremor, 10min each time.Control group and model group grab a fixed at the same time, once daily for 21 days. Detection of left ventricular end diastolic diameter(LVEDD),left ventricular end systolic diameter (LVESD) and left ventricular ejection fraction (LVEF) by Sonos Agilent 5500 color Doppler echocardiography, with LVEF≤45% forsuccessful model. Record the electrocardiogram and ST voltage change of rats after treatment;Elisa was used to detect the content of VEGF in the serum of rats;HE staining was used to  observe  the  pathological  changes  of  myocardial  tissue,  and  the  expression  of  VEGF  in myocardial  infarction  area  was  detected  by  Western  blotting.   Results:Left  ventricular  end diastolic diameter(LVEDD) and left ventricular end systolic diameter(LVESD) of model group were higher  than  control  group(P<0.01),left  ventricular  ejection  fraction(EF)  of  model  group  were lower than the control group(P<0.01);the LVEDD and LVESD value of the EA group were lower than  the  model  group(P<0.01),the  EF  value  is  higher  than  the  model  group(P<0.01).After modeling, the voltage of the ST segment in the model group was significantly higher than that of the  control  group(P<0.01),the  difference  of  VEGF  content  between  model  group  and  control group was statistically significant(P<0.01).After treatment,the ST segment voltage of the EA group was  lower  than  that  of  the  model  group(P<0.01).Compared  with  model  group,the  content  of VEGF in EA group was higher than that of model group(P<0.01).The expression of VEGF protein in the model group was lower than that in the control group(P<0.01),and the expression of VEGF in the myocardial infarction area of the EA group was higher than that of the model group (P<0.01).

Conclusion:   Needling  "Neiguan","Zusanli"  and  "Guanyuan"  can  promote  the  expression  of VEGF in rats of chronic myocardial ischemia,promote angiogenesis,improve heart function,and reduce  myocardial  ischemia  area,which  may  contribute  to  the  prevention  and  treatment  of chronic ischemic heart disease.

Key words:  Ectroacupuncture preconditioning, Myocardial ischemia, VEGF