NEURAL MECHANISM OF THE EFFECT OF ACUPUNCTURE ON MYOCARDIAL ISCHEMIA

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。冠状动脉疾病是北美中老年人死亡的最大原因。这种疾病的治疗还远远不够完美，而且常常伴有副作用。近年来，人们对包括针灸在内的冠状动脉疾病的替代医学和治疗越来越感兴趣。针灸及其更有效的替代疗法——电针（EA），几个世纪以来一直被东方国家的医生认为是治疗许多疾病的有效疗法。世界卫生组织（WHO）列出了40多种针灸可能有效的疾病。就心血管系统而言，心脏疼痛、心律失常和高血压的治疗都属于后一类，一些临床和基础科学报告显示其有效性。然而，大多数西方医生不愿意接受针灸，因为决定其作用的生理机制尚未得到很好的描述。本研究的目的是证明：(1)静息和应激引起的心肌缺血、心律失常和高血压反应在EA的作用下有所降低；(2)缺血反应的机制是心肌氧供需失衡，源于交感自主神经元系统活动增加导致需氧量增加。EA抑制交感神经系统，降低血压，减少氧气需求；(3) EA导致脑干核内产生内啡肽，这种内啡肽能拮抗神经传递，在人脑中可以成像，与交感神经活动的调节有关。研究者先前的动物数据表明，心肌缺血期间心血管功能的改善是由ea诱导的源自躯体神经的感觉神经反射介导的，以减少交感神经的活动。研究人员的具体目标将使我们能够更好地理解和调节交感神经放电活动，这种活动在人类心理和运动压力下引发冠状动脉缺血、心律失常和高血压。研究者还将确定EA调节交感神经流出的中枢神经位置。EA在缺血性心脏病、心律失常和高血压患者中的治疗价值是潜在的临床应用价值。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Coronary artery disease is the greatest cause of death in middle aged and elderly individuals in North America. Treatment for this disease is far from perfect and is often associated with side effects. In recent years there is increasing interest in alternative medicine and therapy for coronary artery disease including acupuncture. Acupuncture and its more potent alternative, electroacupuncture (EA), are therapies that have been recognized for centuries by physicians in Eastern countries to be effective in treating a number of diseases. The World Health Organization (WHO) lists more than 40 conditions for which acupuncture may be effective. With regard to the cardiovascular system, the management of cardiac pain, arrhythmias, and hypertension all fall into the latter category for which some clinical and basic science reports suggest efficiency. However, most Western physicians have been reluctant to accept acupuncture because the physiological mechanisms determining its actions have not been well described. The purpose of this study is to prove: (1) myocardial ischemia, cardiac arrhythmias, and hypertensive responses at rest and provoked by stress are decreased by EA; (2) the mechanism of the ischemic response is an imbalance between myocardial oxygen supply and demand originating as an increase in sympathetic autonomic neurons system activity causing increased oxygen demand. EA inhibits the sympathetic nervous system, decreases the blood pressure and reduces the oxygen demand; (3) EA leads to production of endorphins that antagonize neurotransmission in nuclei of brainstem that can be imaged in the human brain and which are concerned with regulation of sympathetic nerve activity. The investigator's prior data in animals shows that improvements in cardiovascular function during myocardial ischemia are mediated by an EA-induced sensory neural reflex originating in somatic nerves to reduce sympathetic nerve activity. The investigators' specific aims will allow us to better understand and modulate the sympathetic nervous discharge activity that precipitates coronary ischemia, arrhythmias and hypertension in psychological and exercise stress in humans. The investigators also will determine the central neural location of EA modulation of sympathetic outflow. Potential clinical application is the therapeutic value of EA in patients with ischemic heart disease, arrhythmia and hypertension.