电针治疗对大鼠脑缺血后电压门控型钠通道Na(v)1．6表达的影响

Effect of electroacupuncture on the expression of voltage-gated sodium channel Na(v)1.6 after cerebral ischemia in rats

目的观察电针治疗对大鼠脑缺血后电压门控型钠通道Na(v)1.6表达的影响。方法将健康成年雄性SD大鼠105只,随机分为假手术组(15只)、脑缺血组(45只)和电针治疗组(45只)。线栓法制作右侧大脑中动脉永久性闭塞模型。电针治疗组在大鼠清醒后,选取内关、外关、足三里、三阴交穴位行针刺治疗,留针时间30min,1次/d。在缺血后6h,1、2、3 d及7 d观察大鼠神经功能缺损情况,以及纹状体区Na(v)1.6的表达(免疫荧光染色和实时荧光定量PCR法)及脑梗死体积的变化。结果①缺血组和电针治疗组大鼠神经功能缺损表现在缺血后2 d最严重;相同时间点,缺血组比电针治疗组神经功能缺损程度严重(P<0.05)。②免疫荧光染色显示,缺血组和电针治疗组Na(v)1.6的表达均在缺血后1 d达高峰,随后下调。实时荧光定量PCR显示,缺血组6 h～1 d表达上调,1 d表达最强,2～7 d表达呈下调趋势;电针治疗组从缺血6 h开始至缺血7d,Na(v)1.6表达呈下调趋势。上述2种方法均显示,相同时间点,电针治疗组较缺血组Na(v)1.6表达下调(P<0.05)。③缺血组和电针治疗组脑梗死体积均在缺血3 d最大。相同时间点电针治疗组脑梗死体积比缺血组小(P<0.05)。结论 Na(v)1.6可能参与缺血性脑损伤的发病过程。电针治疗可能通过下调Na(v)1.6表达发挥对缺血性脑损伤的保护作用。

Objective To observe the eftect of electroaeupuncture on the expression of voltage-gated sodium channel Na（v）1.6 after cerebral ischemia in rats. Methods A total of 105 healthy adult male Sprague-Dawley rats were randomly allocated into sham operation （ n = 15）, ischemic （ n = 45 ） and elec- troacupuncture （n = 45） groups. A model of permanent right middle cerebral artery occlusion （MCAO） was induced by the intraluminal filament method. After wakening, the rats in the electroacupuncture group were treated with electroacupuncture by choosing the following acupoints： Neiguan, Waiguan, Zusanli, and Sanyinjiao, the needle retaining time was 30 minutes, once a day. Neurological deficit, striatum Na （v） 1.6 expression（immunofluorescence staining and real-time fluorescence quantitative PCR method）, and infarct volume changes in rats were observed at 6 hour, days 1, 2, 3, and 7 after ischemia. Results （1）Nenrological deficit was most severe at day 2 after ischemia in the ischemic group and electroacupuncture group; at the same time point, the neurological deficit in the ischemie group was more severe than that in the electroacupuncture group （P 〈 0.05）. （2）Immunofluorescence staining showed that the expression of Na （v） 1.6reached the peak at dav 1 in both the ischemic and electroacupuncture groups, and then it began to be down-regulated. Real-time quantitative PCR showed that the expression of Na （v） I. 6 was up-regulated from 6 hour to day 1, it was highest at day 1, and the expression showed a downward trend from day 2 to clay 7 ; tile expression of Na （v） 1.6 was down-regulated from 6 hour to day 7 in the electroacupuncture group. At the same time point, the above two methods showed that the expression of Na （v） 1.6 was downregulated iu the electroaeupuneture group compared to the ischemic group （P 〈 0.05）. （3）The infarct volume became the largest at day 3 after ischemia in both ischemie and eleetroaeupuneture groups. At the same time pniut, the infarct volume in eleetroaeupuneture group was smaller than that in the isehemie group （ P 〈0.05）. Conclusion Na （v） 1.6 may be involved in the pathogenic process of isehemie brain injury. Eleetroacupunetare may exert protective effect for isehemie cerebral injury through the down-regulation of the expression of Na （v） 1. 6.