循经取穴改善心肌缺血大鼠心肌细胞能量代谢的腺苷受体间cross-talk机制研究

Coronary heart disease (CHD) is one of these major diseases in modern society, while its most basic pathological change is myocardial ischemia. How to prevent and treat myocardial ischemia effectively is of great significance. It is validated that acupoints selection along meridian can effectively treat myocardial ischemia of coronary heart disease in ancient and modern clinical practice. However, its biological mechanism has not been fully interpreted. In previous study, we explored a variety of neurotransmitters and receptors modulating mechanism underlying acupuncture treatment of myocardial ischemia. What is more, we found that acupuncture is able to evoke purinergic receptor located in the target organ. The modulation effect is the potential key to biological mechanism for acupuncture treatment of myocardial ischemia. Therefore, based on the theory of 'combinatorial receptors web model', this study focuses on the cardiac adenosine receptors in myocardial ischemia rat model. We will utilize techniques such as TUNEL detection, RNA interference to primarily detect the A1, A2a and A2b receptors' expression at heart organ which yields from acupuncture stimulation at Neiguan (PC6). Meanwhile, we shall observe the modulatory effect of those receptors towards energy metabolism of myocardial cells. Secondly, we would observe the expression of A1 receptor and its modulation to energy metabolism of myocardial cells by gene silence of A2a/A2b receptor. Thus these trials can help us elucidate the research hypothesis that the crosstalk between the adenosine A1 receptor and A2a, A2b receptors may optimize the energy metabolism of myocardial cell which is the essential mechanism of acupoints selection along meridian treating myocardial ischemia. Therefore, we may provide high quality scientific evidence to support acupuncture treatment of coronary heart disease by acupoints selection along meridian.

冠心病为重大疾病之一，心肌缺血是其最基本的病理改变，如何有效防治心肌缺血意义重大。古今针灸临床证实循经取穴治疗冠心病心肌缺血疗效肯定，然其生物学机制尚未得到全面阐释。前期研究中，我们探索了多种神经递质和受体介导针刺治疗心肌缺血的作用机制，发现针刺对靶器官腺苷受体的调控作用可能是解释针刺改善心肌缺血生物学机制的关键点。因此，本研究基于"组合受体网络模型"理论，以心肌缺血大鼠模型为研究对象，以心脏腺苷受体为靶点，采用TUNEL检测、RNA干扰等技术，先观察针刺内关对心脏腺苷受体A1、A2a、A2b的表达及受体介导心肌细胞能量代谢的调控作用，再观察A2a/A2b受体基因沉默后，针刺内关对A1受体的表达及其对心肌细胞能量代谢的调控作用，从而论证"腺苷受体A1与A2a/A2b间cross-talk改善心肌细胞能量代谢是循经取穴治疗心肌缺血的作用机制"的假说，为循经取穴治疗冠心病心肌缺血提供理论依据。

本项目以针灸临床切实有效的“循经取穴”原则和经穴脏腑相关理论为立项基础，以人类重大疾病“冠心病”最基本的病理改变“心肌缺血”为研究载体，鉴于针刺多靶点、多层次的网络整合效应与嘌呤能受体间cross-talk所形成的“组合受体网络”效应之间具有相同之处，本研究以心脏腺苷受体为靶点，以腺苷 A1与 A2a/A2b受体间cross-talk为切入点，采用TUNEL检测、RNA干扰等技术，观察循经取穴针刺内关对心肌缺血损伤的保护效应并阐释其作用机制。研究结果表明：循经取穴针刺内关具有抑制心肌缺血大鼠ST段抬高、提高心肌组织的耗氧量、减少心肌梗死面积、减少心肌细胞凋亡率、改善心肌细胞能量代谢等保护心肌缺血损伤的靶器官效应；循经取穴针刺内关可能通过上调腺苷受体A1及A2b的表达来增加心机耗氧量、提高心肌ATP含量、减少心肌AMP含量、增加心肌ADO含量，从而减少心肌缺氧导致的心脏损伤，而A1与A2b的交叉调控很可能在心肌损伤过程中起到了至关重要的作用。本研究论证了“腺苷受体 A1与 A2b间的cross-talk是循经取穴治疗心肌缺血的作用机制”的研究假说，为针刺改善心肌缺血的机制阐释上提供了新的思路和方向，也为循经取穴治疗冠心病心肌缺血提供新的科学依据。