RESUMO
[Objective] To investigate the influence of injection of substance P (SP) and its antagonist into locus ceruleus on electroacupuncture of Neiguan for acute myocardial ischemia (AMI). [Methods] Rabbit model of AMI was set up by ligating left ventricular branch of coronary artery. Forty-nine rabbits were allocated to five groups: Group A (the control group), Group B (electroacupuncture of Neiguan), Group C (injection of SP), Group D (electroacupuncture of Neiguan and injection of SP) and Group E (electroacupuncture of Neiguan and injection of SP antagonist) . Locus ceruleus was located by cerebral stereotaxic apparatus. Dynamic changes of ST segment of electrocardiogram and morphological feature of myocardium were observed. [ Results ] Injection of SP promoted the recovery of AMI and enhance the effect of electroacupuncture of Neiguan for AMI. However, the above effects were counteracted by the injection of SP antagonist. [Conclusion] SP plays an important role in reducing the damage of AMI on electroacupuncture of Neiguan and may serve as an important mediator for the connection of Neiguan and the heart.