针刺对大鼠脑缺血后海马突触可塑性的促进作用

目的:探讨针刺治疗缺血性脑血管疾病的机制。方法:采用热凝闭大鼠大脑中动脉致局灶性脑缺血模型,随机分为假手术组、缺血组和治疗组,观察针刺对脑缺血后缺血同侧海马齿状回(DG)突触可塑性的影响。结果:缺血2周后缺血同侧海马齿状回兴奋性突触后电位(EPSP)、群峰电位(PS)的I/O曲线幅度均显著降低(P<0.05);和缺血组相比,治疗组EPSP、PS的I/O曲线幅度均显著升高(P<0.01,P<0.05),和假手术组相比无明显差异(P>0.05)。EPSP的长时程增强(LTP)幅度在缺血2周后明显升高(P<0.05);治疗组与假手术组相比明显升高(P<0.05),与缺血组无明显差异(P>0.05)。PS的LTP幅度在缺血2周后明显降低(P<0.05),治疗组明显高于缺血组(P<0.05),与假手术组相比无明显差异(P>0.05)。EPSP的长时程抑制(LTD)幅度在缺血2周后明显降低(P<0.05),治疗组与假手术组相比明显降低(P<0.05),与缺血组相比无明显差异(P>0.05)。PS的LTD幅度缺血组与假手术组无明显区别(P>0.05);治疗组与假手术组相比有所升高(P<0.05),与缺血组相比无明显差异(P>0.05)。结论:针刺对缺血引起的海马DG区I/O曲线的EPSP、PS的幅度变化起保护作用;针刺能修复缺血造成海马DG区PS的LTP诱导的损害;针刺对缺血后海马DG区EPSP的LTD的诱导无明显影响,对PS的LTD诱导有一定的提高作用。

The Improvement of Synaptic Plasticity in the Rat Dentate Gyrus after Stroke by Acupuncture

Objective: To observe effect of acupuncture on synaptic plasticity in the rat dentate gyrus after stroke.Methods: Thirty-six male adult Wistar rats were divided into 3 groups:sham-operation group,ischemia group and acupuncture group.Models of focal cerebral ischemia were established by heat coagulating occlusion of the middle cerebral artery.The changing of synaptic plasticity in the rat dentate gyrus and the influence of acupuncture on the process was studied 2 weeks after ischemia.Results: Compared with the control rats the current-voltage curve of EPSP slope in ischemia rate was significant depressed(P<0.05).Ischemia reduced the amplitudes of the I/O curve of PS(P<0.05) significantly.Compared with the ischemia rate the current-voltage curve of EPSP slope in acupuncture rate was significant enhanced(P<0.05).Acupuncture enhanced the amplitudes of the I/O curve of PS(P<0.05) significantly.There was no statistical difference between the sham-operation group and acupuncture group(P>0.05).The amplitudes of PS LTP was also reduced by ischemia(P<0.05).The acupuncture enhanced the amplitudes of PS LTP(P<0.05) significantly.The amplitudes of EPSP LTP was enhanced by ischemia(P<0.05),The acupuncture could not enhanced the amplitudes of EPSP LTP(P>0.05).The amplitudes of EPSP LTD was also reduced by ischemia(P<0.05).The acupuncture could not enhanced the amplitudes of EPSP LTD(P>0.05).The amplitudes of PS LTD had not significant difference between control and ischemia(P>0.05).Compared with the ischemia rate the acupuncture enhanced the amplitudes of PS LTD(P<0.05) significantly.The amplitudes of PS LTD had not significant difference between control and acupuncture(P>0.05).Conclusion:Acupuncture has a protective role in the magnitude of changes in EPSP and PS of I/O curve in the DG induced by ischemia,and can restore the injury induced by LTP of PS in the DG following ischemia.However,It has no significant effect on the induction of LTD of EPSP in the DG following ischemia,and can enhance the induction of LTD of PS.