β-肾上腺素能受体介导电针内关穴改善缺血性心肌损伤的机制研究

发布时间：2018-06-25 19:08

本文选题：电针 + 内关穴　；参考：《北京中医药大学》2014年硕士论文

【摘要】：心肌缺血性疾病,属于中医学“胸痹”“真心痛”“厥心痛”的范畴。随着人们生活水平的显著提高,心肌缺血性疾病已成为全世界发病率和死亡率均非常高的疾病之一,严重威胁人类的健康和生命。多年来,现代医学在阐明心肌缺血发病机制以及寻找有效的预防和治疗手段方面进行了大量的研究。迄今,除了经典的传统抗凝扩冠药,和后来发展的支架搭桥等外科手术外,其它防治心肌缺血性损伤的办法还是不多,至今该病的发病率和死亡率仍然高居不下。针灸作为一种简、便、验的预防和治疗手段,早在《黄帝内经》中就有关于针灸治疗“胸痹”,“心痛”的记载。大量的古代文献、临床经验以及现代研究均显示：针刺对缺血心肌具有较为确切的保护作用,如缓解冠心病病人心绞痛、胸闷等临床症状,改善ECG-ST-T及左心功能等等。因此,找到关于针刺如何发挥改善心肌缺血性损伤作用的途径,具有重要的临床意义和价值,同时将有助于为针刺改善冠心病心肌缺血性疾病提供科学基础。研究证明,急性心肌缺血时,交感神经及心脏-肾上腺素受体过度激活,导致细胞内钙超载,从而引起心肌缺血性损伤。过去有关针灸方面的研究显示：针刺效应可通过影响交感神经系统的兴奋性而来发挥改善心肌缺血性损伤的作用。众所周知,交感神经的主要靶受体是p-肾上腺素能受体(β-AR),同时,β-AR也是心脏中最重要的受体,故交感神经对心脏的调节和控制作用主要是通过p-AR来完成的。由此可知,针刺效应的作用极有可能通过影响心脏交感神经系统,从而进一步作用于交感神经系统的靶受体p-肾上腺素能受体,最终起到改善缺血性心肌损伤的作用。实验目的：本研究通过采用结扎冠状动脉左前降支的大鼠急性心肌缺血模型,以及小鼠游泳疲劳运动模型,来观察电针内关穴对缺血心肌的保护作用。进一步探讨p-AR介导电针内关穴改善缺血性心肌损伤的机制研究,为针刺防治心肌缺血性疾病提供临床指导意义以及理论基础。实验方法： 1.第一部分实验：选用雄性成年Wistar大鼠32只,体重235±15g。将大鼠随机分为四组：正常组(NC组)、模型组(Model组)、电针组(EA组)和心得安组(EAP组),每组各8只。Model、EA和EAP组于麻醉后行冠脉结扎术,且全程记录Ⅱ导联心电图。NC组仅穿线,不做其他处理。EA组于每次麻醉后电针内关30min(电针参数：强度3mA,频率20Hz); EAP组于麻醉后先腹腔注射p-AR阻断剂——心得安(10mg/kg),15min后再电针“内关"30min,连续3天。通过观察大鼠心电图ST段幅值的变化、心律失常评分和心肌梗塞面积来明确电针“内关”穴改善缺血性心肌损伤的效应,并探讨p-AR是否参与介导了上述针刺效应。 2.第二部分实验：选用野生型C57BL/6小鼠及与其同品系的β1/β2-AR双敲小鼠,各24只,雄性,体质量18-25g。C57BL/6小鼠随机分为三组：对照组(Control组)、游泳游泳疲劳组(疲劳组,Fatigue组)和电针组(EA组),每组各8只。Control组不给予任何处理；Fatigue组只给予游泳疲劳运动,不做其他处理；EA组将小鼠放入自制的黑色鼠套后电针双侧“内关”30min(电针参数：强度0.5mA,频率2Hz),连续7天。β1/β2-AR双敲小鼠的处理方法同上。本实验部分通过游泳疲劳运动模型来观察电针“内关”穴改善游泳疲劳诱发的心肌缺血效应,并引用β1/β2-AR敲除小鼠来进一步观察p-AR是否参与介导了电针“内关”穴改善缺血性心肌损伤的针刺效应。实验结果： 1.p-肾上腺素能受体介导电针抗大鼠急性心肌缺血的机制研究 1.1电针“内关”穴对急性心肌缺血大鼠心电图ST段幅值的影响大鼠急性心肌缺血造模前,NC、Model、EA和EAP组ST段幅值均正常,四组之间没有显著的统计学差异(P0.05)。经3天干预后,除NC组与Baseline比较无明显变化外,Model组心电图ST段幅值有明显的抬高(P0.01),说明造模较成功。EA组在经过3天的电针干预后其心电图ST段幅值基本接近于正常,与Model组比较有明显的降低(P0.01),而EAP组在经过3天的电针干预后ST段幅值与Model组比较无统计学差异(P0.05),与Baseline和EA组比较均有明显抬高(P0.01)。 1.2电针“内关”穴对急性心肌缺血大鼠心律失常评分的影响在急性心肌缺血造模前,NC、Model、EA和EAP组各组大鼠心律失常评分均为O。经3天干预后,除NC组与Baseline比较无变化外,Model组出现了明显的房性／室性心律失常(P0.01)。而EA组经过3天的电针干预后,心律失常评分与Model组比较明显降低(P0.05),而EAP组在经过3天的电针干预后心律失常评分与Model组比较无统计学差异(P0.05),与Baseline和EA组比较均有显著性差异(P0.05,P0.01)。 1.3电针“内关”穴对急性心肌缺血大鼠心肌梗塞面积的影响造模前,各组大鼠心肌梗塞面积均为0。经过3天干预后,与NC组比较,Model组和EAP组心肌梗塞面积均明显增加(P0.01)。在而经过3天电针干预后,EA组心肌梗塞面积明显低于与Model和EAP组(P0.01)。 2、β-肾上腺素能受体介导电针抗小鼠游泳疲劳的机制研究 2.1电针“内关”穴对游泳疲劳C57BL/6小鼠各项指标的影响 Control组在Baseline.干预第1天至第7天后心电图ST段幅值、心率和心律失常评分均未见明显的改变。游泳疲劳运动后,Fatigue组和EA组小鼠均出现心电图ST段幅值抬高、心率减慢和心律失常评分增加等急性心肌缺血的征象,各项指标与相应的Baseline比较,均有明显的统计学差异(P0.01),经过7天的干预后,Fatigue组ST段幅值、心率和心律失常评分均没有变化,无统计学差异(P0.05),而EA组在经过7天的电针“内关”穴干预后,上述指标除心率没有变化外,其他均基本接近于正常水平,与Fatigue组比较有明显的改善(P0.01)。 2.2电针“内关”穴对游泳疲劳β1/β2-AR敲除小鼠各项指标的影响 Control组在Baseline、第1天至第7天后心电图ST段、心率和心律失常评分均未见明显的改变。游泳疲劳运动后,Fatigue组和EA组小鼠均出现心电图ST段幅值抬高、心率减慢和心律失常评分增加,与Baseline比较,均有明显的统计学差异(P0.01),经过7天的干预后,EA组与Fatigue组比较,ST段幅值、心率和心律失常评分均没有变化,无统计学差异(P0.05)。实验结论：电针“内关”穴可以有效地改善急性心肌缺血大鼠引起的心电图ST段幅值的抬高、心律失常评分增加和心肌梗塞面积的扩大；另一方面,电针“内关”穴亦可以改善由游泳疲劳小鼠诱发的心电图ST段幅值的异常抬高以及心律失常的发生。而电针干预前应用β-AR阻断剂或敲除β-AR后,电针干预改善心肌缺血的效应亦被阻断。以上结果表明：电针“内关”穴可以有效地改善心肌缺血征象,且β-AR参与介导了上述针刺效应。
[Abstract]:Myocardial ischemic disease, which belongs to the category of "chest pain", "heartpain" and "syncope" in traditional Chinese medicine. With the remarkable improvement of people's living standard, myocardial ischemic disease has become one of the diseases with high morbidity and mortality all over the world. It is a serious threat to human health and life. In addition to the classical traditional anticoagulant crowns, and the subsequent development of the scaffolding, there are still few other methods to prevent and cure myocardial ischemia, and the incidence and mortality of the disease still remain high. For a simple, simple, effective means of prevention and treatment, there is a record of "chest Bi" and "heart pain" in acupuncture treatment of "chest Bi" and "heart pain". A large number of ancient literature, clinical experience and modern research all show that acupuncture has a more precise protective effect on ischemic myocardium, such as relieving angina pectoris and chest tightness in patients with coronary heart disease. It can improve the function of ECG-ST-T and left heart and so on. Therefore, it is of important clinical significance and value to find the way to improve the effect of acupuncture on ischemic injury of myocardium. It will also help to provide a scientific basis for the improvement of coronary heart disease of coronary heart disease.
Studies have shown that the excessive activation of sympathetic and cardiac adrenergic receptors in acute myocardial ischemia leads to intracellular calcium overload and leads to myocardial ischemic injury. Previous studies on acupuncture and moxibustion have shown that the effect of acupuncture can improve the myocardial ischemia injury by affecting the excitability of the sympathetic nervous system. It is well known that the main target receptor of the sympathetic nerve is the p- adrenergic receptor (beta -AR), and that beta -AR is also the most important receptor in the heart. The regulation and control of the sympathetic nerve to the heart is accomplished mainly through p-AR. Thus, the effect of the acupuncture effect is very likely to be further affected by the cardiac sympathetic nervous system. The target receptor p- adrenergic receptor acting on the sympathetic nervous system eventually plays an important role in improving ischemic myocardial damage.
Objective:
In this study, a rat model of acute myocardial ischemia with a left anterior descending coronary artery and a swimming fatigue model in mice were used to observe the protective effect of electroacupuncture Neiguan on the ischemic myocardium, and further explore the mechanism of p-AR mediated the improvement of ischemic myocardium by Electroacupuncture at Neiguan point. For clinical guidance and theoretical basis.
Experimental methods:
1. the first part of the experiment: 32 male adult Wistar rats and 235 + 15g. rats were randomly divided into four groups: normal group (group NC), model group (group Model), electroacupuncture group (group EA) and propranolol group (group EAP), each group of 8.Model, EA and EAP group underwent coronary artery ligation after anesthesia, and the whole course record of lead electrocardiogram in.NC group was not done. The other treatment of.EA group was 30min (Electroacupuncture Parameters: 3mA, frequency 20Hz) after each anaesthesia. Group EAP was injected with p-AR blocker, 10mg/kg, 15min and Electroacupuncture of "Neiguan" for 3 days after anesthesia. The amplitude of ST segment, arrhythmia score and myocardial infarction area were observed. To clarify the effect of electroacupuncture at "Neiguan" on improving ischemic myocardial injury, and to explore whether p-AR participates in the above-mentioned acupuncture effect.
2. the second part of the experiment: the wild type C57BL/6 mice and the same strain of beta 1/ beta 2-AR double knockout mice, each 24, male, body mass 18-25g.C57BL/6 mice were randomly divided into three groups: the control group (Control group), swimming and swimming fatigue group (fatigue group, Fatigue group) and Electroacupuncture group (EA group), each group of 8.Control groups did not give any treatment; Fatig In group UE, only swimming fatigue was given and no other treatment was done. In group EA, the mice were put into the self-made black rat sleeve after the Electroacupuncture of the bilateral "Neiguan" 30min (Electroacupuncture Parameters: intensity 0.5mA, frequency 2Hz) for 7 days. The treatment method of beta 1/ beta 2-AR double knockout mice was the same. The effect of myocardial ischemia induced by good swimming fatigue, and using beta 1/ beta 2-AR knockout mice to further observe whether p-AR is involved in mediating the acupuncture effect of electroacupuncture "Neiguan" on the improvement of ischemic myocardial injury.
Experimental results:
Mechanism of 1.p- adrenergic receptor mediated Electroacupuncture against acute myocardial ischemia in rats
1.1 effect of electroacupuncture at "Neiguan" point on ST segment amplitude of electrocardiogram in rats with acute myocardial ischemia
Before the model of acute myocardial ischemia in rats, the amplitude of ST segment in NC, Model, EA and EAP groups were all normal. There was no significant difference between the four groups (P0.05). After 3 days of dry prognosis, the amplitude of ST segment in the Model group was obviously elevated (P0.01) except the NC group and Baseline, which showed that the prognosis of the model was more successful after 3 days of electroacupuncture. The amplitude of the ST segment of the electrocardiogram was basically close to the normal, compared with the Model group (P0.01), while the ST segment amplitude in the EAP group after 3 days of electroacupuncture was not significantly different from that in the Model group (P0.05), and there was a significant elevation compared with the Baseline and the EA group (P0.01).
1.2 effect of electroacupuncture at "Neiguan" point on arrhythmia score in rats with acute myocardial ischemia
Before the model of acute myocardial ischemia, the arrhythmia scores of NC, Model, EA and EAP groups were all O. after 3 days of dry prognosis. Except the NC group and Baseline, the Model group had obvious atrial / ventricular arrhythmia (P0.01). While the EA group after 3 days of electroacupuncture, the arrhythmia score was significantly lower than the Model group (P0.05). There was no significant difference in arrhythmia score between group EAP and Model group after 3 days of electroacupuncture intervention (P0.05), and there was significant difference compared with group Baseline and EA (P0.05, P0.01).
1.3 effect of electroacupuncture at "Neiguan" point on myocardial infarction area in rats with acute myocardial ischemia
The infarct area of all rats in each group was 0. after 3 days of dry prognosis. Compared with the NC group, the area of myocardial infarction in group Model and EAP increased significantly (P0.01). After 3 days of electrical acupuncture, the area of myocardial infarction in group EA was significantly lower than that in group Model and EAP (P0.01).
Mechanism of 2, beta adrenergic receptor mediated Electroacupuncture against swimming fatigue in mice
2.1 effect of electroacupuncture at Neiguan on various indexes of swimming fatigue C57BL/6 mice
In group Control, the amplitude of ST segment of electrocardiogram, heart rate and arrhythmia score were not significantly changed after Baseline. intervention first days to seventh days. After swimming fatigue, all Fatigue and EA group mice had the signs of acute myocardial ischemia, such as ST segment elevation, heart rate slowing and arrhythmia score, and the corresponding Ba Compared with Seline, there were significant statistical differences (P0.01). After 7 days of prognosis, the amplitude of ST segment, heart rate and arrhythmia score of group Fatigue did not change, and there was no statistical difference (P0.05), but in group EA, after 7 days of electroacupuncture "Neiguan" point, the above indexes were basically close to the normal level except the heart rate, and the other were almost the same as Fa. There was a significant improvement in group tigue (P0.01).
2.2 effects of electroacupuncture at Neiguan on the indexes of swimming fatigue 1/ 2-AR mice
Control group had no significant changes in heart rate and arrhythmia score at Baseline, first days to seventh days, heart rate and arrhythmia score. After swimming fatigue, the ST segment elevation, heart rate slowing and arrhythmia score increased in both Fatigue and EA groups. There were significant statistical differences (P0.01) after 7 days, compared with the Baseline ratio (P0.01). After intervention, there was no significant difference in the amplitude of ST segment, heart rate and arrhythmia score between group EA and group Fatigue (P0.05).
Experimental conclusions:
Electroacupuncture of "Neiguan" point can effectively improve the elevation of the amplitude of ST segment of ECG induced by acute myocardial ischemia in rats, increase the score of arrhythmia and enlarge the area of myocardial infarction. On the other hand, the electroacupuncture "Neiguan" point can also improve the abnormal elevation of the amplitude of the ST segment of electrocardiogram induced by the swimming fatigue mice and the arrhythmia. The effect of electroacupuncture intervention to improve myocardial ischemia was also blocked before using the beta -AR blocker or knockout beta -AR before electroacupuncture intervention. The results showed that the electroacupuncture "Neiguan" point could effectively improve the myocardial ischemia signs, and the beta -AR was involved in mediating the above acupuncture effect.
【学位授予单位】：北京中医药大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R245

【参考文献】