不同刺激参数及其组合对电针诱导大鼠脑缺血耐受效应的影响

Effects of Different stimulating parameters and their various combinations on electroacupuncture-induced cerebral ischemic tolerance in rats

目的 :研究电流强度、波形、频率三种刺激因素对电针诱导脑缺血耐受效应的影响 ,寻求最佳的刺激参数组合。方法 :应用嵌套设计 ,将 2 10只SD大鼠随机分为 35组 (每组 6只 ) ,分别为空白对照组、戊巴比妥钠组及 33个电针组。最后一次处理 2 4h后采用颈内动脉尼龙线线栓法致右大脑中动脉栓塞 (12 0min)模型。再灌注 2 4h行神经功能障碍评分 (NDS)后取脑 ,经TTC染色计算脑梗死容积。结果 :脑梗死容积 :三种电流强度 (1mA、2mA、3mA )间差异无显著性意义 (P >0 0 5 ) ;三种波形间差异有非常显著性意义 (P <0 0 1) ;2～ 10 0Hz各频率间差异有极显著性意义(P <0 0 0 0 1)。 33个电针组分别与空白组梗死容积比较 ,除连续波 1mA +30Hz、2mA +30Hz、1mA +10 0Hz、2mA +10 0Hz、3mA +10 0Hz ,间断波 1mA +10 0 / 0Hz、2mA +10 0 / 0Hz、3mA +10 0 / 0Hz差异无显著性意义外 ,其余差异均有显著性意义 (P <0 0 5 )。其中疏密波 2 / 15Hz、2 / 30Hz以及连续波 2Hz刺激时梗死灶最小。各电针组NDS与空白组比较差异均有显著性意义 (P均<0 0 5 )。结论 :电针重复刺激大鼠“百会”穴可诱导脑缺血耐受 ,刺激波形和频率是更为重要的刺激参数。频率为疏波 2Hz、密波 15～

Objective To investigate the effect of different stimulating parameters including current intensity, frequency and wave form on electroacupuncture-induced cerebral ischemic tolerance so as to obtain the best combination of the stimulating parameters. Methods Two hundred and ten male SD rats were randomly divided into 35 groups: control group, pentobarbital group and 33 electroacupuncture groups, 6 rats in each group. Twenty four hours after the last treatment, the right middle cerebral artery was occluded for 120 min, and the neurological deficit scores (NDS) were evaluated at 24 h after reperfusion, and then the infarct size was determined by TTC staining. Results There was no significant difference among the three current intensity (1 mA, 2 mA and 3 mA) for infarct size (P>0.05), but there was a very significant difference among the three wave forms (P<0.01), and among the frequencies from 2 Hz to 100 Hz (P<0.0001) respectively. The cerebral infarct size in most electroacupuncture groups decreased. The groups of 2/15 Hz, 2/30 Hz and 2 Hz showed the smallest cerebral infarct size. The NDS in all the electroacupuncture groups were lower than that in the controls (P<0.05). Conclusion Frequency and wave form play more important roles in the electroacupuncture-induced cerebral ischemic tolerance than current intensity, with the best frequencies from 2 Hz to 30 Hz.