星状神经节阻滞对大鼠急性心肌梗死后室性心律失常的影响

Effect of stellate ganglion blockade on ventricular arrhythmia in rats with acute myocardial infarction

目的探讨星状神经节阻滞(stellate ganglion blockade, SGB)对大鼠急性心肌梗死(myocardial infarction, MI)后室性心律失常(ventricular arrhythmia, VA)的影响。方法雄性SPF级SD大鼠45只,体重200~250 g,随机数字表法分为三组:假手术组(S组)、MI组和SGB组,每组15只。结扎冠状动脉制备MI模型。记录VA诱发率、室颤阈值和有效不应期,以及血浆超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。采用ELISA法测定血浆儿茶酚胺抑素(catestatin, CST)浓度。结果造模后1周,S组、MI组和SGB组分别有2只、1只和1只大鼠死亡。与S组比较,MI组VA诱发率明显升高(P<0.05),MI组和SGB组室颤阈值和有效不应期明显减小(P<0.05)。与MI组比较,SGB组VA诱发率明显降低,室颤阈值和有效不应期明显增加(P<0.05)。与S组比较,MI组血浆CST浓度和MDA含量明显升高,SOD活性明显降低(P<0.05)。与MI组比较,SGB组CST浓度和MDA含量明显降低,SOD活性明显升高(P<0.05)。结论星状神经节阻滞可抑制心肌梗死后室性心律失常的发生,其机制可能与降低交感流出和抗氧化损伤有关。

Objective To investigate the effect of stellate ganglion blockade(SGB) on ventricular arrhythmia(VA) in rats with acute myocardial infarction(MI). Methods Forty-five Sprague-Dawley rats were divided into three groups(n = 15 for each group) according to random number table, including sham operation group(group S), MI group(group MI) and SGB group(group SGB). The MI model rats were prepared by ligation of coronary artery. The occurrence of VA, ventricular fibrillation(VF) cutoff and effective refractory period(ERP) in acute myocardial infarction were assessed. The activity of superoxide dismutase(SOD) and levels of malondialdehyde(MDA) were recorded and plasma concentration of catestatin(CTS) were measured by ELISA. Results Compared with group S, the inducibility of VA after MI was increased in group MI, VF cutoff and ERP were decreased significantly in groups MI and SGB(P < 0.05). Compared with group MI, the inducibility of VA was decreased, whereas the VF cutoff and ERP were increased in group SGB(P < 0.05). Compared with group S, the expression of CTS and MDA were increased significantly, SOD activity was decreased(P < 0.05). Compared with group MI, the concentration of CST and MDA levels were lower, SOD activity was higher(P < 0.05). Conclusion SGB could inhibit VA after MI via inhibiting the release of lipoperoxidation.