王新凤,杨予白,谢雯,张莉
WANG Xinfeng,YANG Yubai,XIE Wen,ZHANG Li

• 1:西安交通大学医学院生理学与病理生理学系

摘要(Abstract)：

目的:研究诱导成年大鼠海马CA1区长时程压抑(long-term depression,LTD)的有效刺激参数及其受体机制。方法:成年雄性SD大鼠断头取脑制作海马脑薄片,采用细胞外场电位记录技术,用不同刺激参数刺激海马CA1区Schaffer传入纤维,记录海马CA1区LTD,寻找有效探讨诱导成年大鼠海马CA1区LTD的刺激参数及其受体机制。结果:双脉冲间隔(paired-pulse interval,PPI)为200 ms,频率1 Hz,900对双脉冲为1组,共2组,组间隔10 min的双脉冲低频刺激(paired-pulse low frequency stimulation,PP-LFS)能够有效诱导海马CA1区LTD,60 min和120 min测定其细胞外场兴奋性突触后电位(fEPSP)斜率,结果分别为前对照的(72.33±3.19)%和(69.11±2.80)%;与PP-LFS相同、仅仅刺激强度增加1倍的高强度的双脉冲低频刺激(high-intensity paired-pulse low frequency stimulation,HI-PP-LFS)也能有效诱导海马CA1区LTD,60 min和120 min测定其细胞外场兴奋性突角后电位(fEPSP)斜率,结果分别为前对照的(50.75±2.10)%和(50.90±5.52)%;NMDA受体拮抗剂APV能有效阻断PP-LFS和HI-PP-LFS诱导的LTD。结论:PP-LFS可有效诱导成年大鼠海马CA1区LTD,HI-PP-LFS可诱导产生更大幅度的LTD,且这种LTD是NMDAR依赖性的。
Objective: To investigate the induction protocol and receptor mechanism of long-term depression( LTD) in hippocampal CA1 in adult rat. Methods: Standard extracellular recording technique was used. Field EPSP( fEPSP) evoked by Schaffer collateral stimulation were recorded from the CA1 subfield of adult rat hippocampal slices. Results: LTD was induced by 2 groups of paired-pulse low frequency stimulation( PP-LFS),which consisted of 900 paired-pulses( 200 ms interval) at 1 Hz for 10 min. The percentage of depotentiation of slope of field EPSP( fEPSP) was( 72. 33 ± 3. 19) %and( 69. 11 ± 2. 80) % in 60 min and 120 min after the induction. Then higher intensity PP-LFS was tested( HI-PP-LFS,twice the intensity as test stimulation),which induced significant LTD. The percentage of depotentiation of slope of field EPSP( fEPSP) was( 50. 75 ± 2. 10) % and( 50. 90 ±5. 52) %. NMDA receptor antagonist APV can effectively block the PP-LFS and HI-PP-LFS induced LTD. Conclusions: PP-LFS can effectively induct adult rat hippocampal CA1 region LTD,and HI-PPLFS can effectively induct significant LTD,which is NMDARs dependent.

关键词(KeyWords)： 海马;CA1;长时程增强;NMDA受体;电刺激;大鼠,Sprague-Dawley
hippocampus;CA1;long-term depression;NMDARs dependent;electric stimulation;rats,Sprague-Dawley

Abstract:

Keywords:

基金项目(Foundation): 中国博士后科学基金(2013M540760);; 中央高校基本科研业务费专项资金(2014xjj 08143031)

作者(Author): 王新凤,杨予白,谢雯,张莉
WANG Xinfeng,YANG Yubai,XIE Wen,ZHANG Li

DOI: 10.19367/j.cnki.1000-2707.2014.05.015

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