电针水沟穴对脑梗死模型大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基mRNA表达的影响

Effects of electroacupuncture at Shuigou(GV 26)acupoint on the m RNA expression of L-type calcium channelα1C subunit and TRPC6 subunit in cerebral vascular smooth muscle of model rats with cerebral infarction

目的观察电针水沟穴对脑梗死模型大鼠脑血管平滑肌中细胞膜电压依赖性钙通道(VDCC)L型钙通道α1C亚基及受体门控钙通道(ROCC)瞬时受体电位通道6(TRPC6)亚基m RNA表达的影响。方法将130只SPF级雄性Wistar大鼠采用随机数字表法分为空白组(10只)、假手术组(40只)、模型组(40只)、电针组(40只)4组,除空白组外,其余3组又随机分为术后3 h、6 h、12 h、24 h 4个时相,每个时相10只。以线栓法复制大脑中动脉闭塞(MCAO)大鼠模型。电针组在造模后即刻针刺水沟穴,以韩氏电针仪刺激20 min。各组大鼠分别于相应时间处死,在外科显微镜下分别分离、剪取梗死侧的大脑前动脉、中动脉、后动脉各8 mm,通过实时荧光定量聚合酶链反应(PCR)检测各组不同时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA的相对表达量。结果与空白组和假手术组比较,模型组各时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA相对表达量均明显上调,差异有统计学意义(P<0.05或P<0.01);与模型组比较,电针组各时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA相对表达量均明显下调,差异有统计学意义(P<0.05或P<0.01)。结论电针干预能显著抑制MCAO模型大鼠脑血管平滑肌中VDCC L型钙通道α1C亚基及ROCC TRPC6亚基m RNA表达的上调,从而抑制缺血后血管平滑肌痉挛,增加脑梗死区周围血流灌注。

Objective To observe the effects of electroacupuncture at Shuigou(GV 26)acupoint on the m RNA expression of cytomembrane voltage-dependent calcium channels(VDCC)L-type calcium channelα1C subunit and receptor-operated calcium channels(ROCC)transient receptor potential channel 6(TRPC6)subunit in cerebral vascular smooth muscle of model rats with cerebral infarction.Methods Totally 130 SPF grade male Wistar rats were divided into 4 groups including blank group(10 rats),sham operation group(40 rats),model group(40 rats)and electroacupuncture group(40 rats).Except the blank group,the remaining 3 groups were randomly divided into 4 time phases of postoperative 3 hours,6 hours,12 hours and 24 hours,with 10 rats in each time phase.Thread embolism was used to replicate middle cerebral artery occlusion(MCAO)rat model.In the electroacupuncture group,Shuigou(GV 26)acupoint was acupunctured immediately after establishing models and stimulated by HAN’s acupoint nerve stimulator for 20 minutes.Rats in each group were executed at corresponding time respectively,and 8 mm of the anterior,middle and posterior cerebral arteries on the infarcted side were separated and cut respectively under the surgical microscope.The relative m RNA expression quantity of L-type calcium channelα1C subunit and TRPC6 subunit in cerebral vascular smooth muscle of rats in different time phases was detected by realtime fluorescence quantitative polymerase chain reaction(PCR).Results Compared with that in the blank group and sham operation group,the relative m RNA expression quantity of L-type calcium channelα1C subunit and TRPC6 subunit in cerebral vascular smooth muscle of rats in the model group were significantly up-regulated at all time phases,and the difference was statistically significant(P<0.05 or P<0.01).Compared with that in the model group,the relative m RNA expression quantity of L-type calcium channelα1C subunit and TRPC6 subunit in cerebral vascular smooth muscle of rats in electroacupuncture group were significantly down-regulated at all time phases,and the difference was statistically significant(P<0.05 or P<0.01).Conclusion Electroacupuncture intervention can significantly inhibit the up-regulation of m RNA expression of VDCC L-type calcium channelα1C subunit and ROCC TRPC6 subunit in cerebral vascular smooth muscle of MCAO model rats,thereby inhibiting vascular smooth muscle spasm after ischemia and increasing peripheral bloodflow perfusion in the area around cerebral infarction.