在体大鼠海马Schaffer-CA1条件化双通路与海马组合突触可塑性  

Hippocampal Combinatorial Plasticity Induced by Conditioning of Converging Schaffer-CA1 Pathways in Rat in vivo

作　　者：曹栋[1,2] 曹军[3] 郝伟[1] 徐林[1,3] 

机构地区：[1]中南大学附属湘雅二医院精神卫生研究所,湖南长沙410011 [2]南京医科大学附属脑科医院,江苏南京210029 [3]中国科学院昆明动物研究所,云南昆明650223

出　　处：《Zoological Research》2009年第4期396-400,共5页动物学研究（英文）

基　　金：国家科技支撑计划(十一五)(2007BAI07B01);国家自然科学基金项目(30530250)

摘　　要：在戊巴比妥钠麻醉的Sprague-Dawley大鼠上,运用海马Schaffer-CA1双通路条件化作用(低频配对,600对脉冲,5Hz,配对刺激相应的兴奋性突触后电位峰值时间间隔为10ms)在两条Schaffer-CA1条件化通路上同时诱导出突触可塑性,呈现出海马组合突触可塑性。结果显示:不管海马Schaffer-CA1双通路独立与否,双通路条件化作用均可以同时诱导出长时程增强(long-term potentiation,LTP)和长时程抑制(long-term depression,LTD),呈现出LTP/LTD组合突触可塑性。结果表明:海马Schaffer-CA1双通路技术,可实现海马突触可塑性的双向诱导,可塑性的方向取决于突触的自身状态。由此提示,与传统的高频诱导LTP低频诱导LTD相比,在海马Schaffer-CA1双通路条件化作用诱导出的组合突触可塑性可以更好地编码海马相关的学习记忆,体现了海马突触可塑性的灵活性与稳定性。Hippocampal plasticity in two conditioning pathways, i.e. hippocampal combinatorial plasticity, can be induced by conditioning of converging Schaffer-CA1 pathways in Sprague-Dawley rats under pentobarbital sodium anesthesia. During conditioning, paired pulses were delivered at 5 Hz （600pairs） and the inter-peak interval of the field excitatory postsynaptic potentials （fEPSP） of the paired-pulse stimulation was 10ms. Our results showed that long-term potentiation （LTP） and long-term depression （LTD） might be induced simultaneously by conditioning of two pathways whether two conditioning pathways were independent or not. Thus hippocampal combinatorial plasticity, i.e. LTP/LTD, can be induced successfully. Our results demonstrated that conditioning paradigm could enable the induction of bidirectional hippocampal synaptic plasticity and the direction of synaptic plasticity was determined by the state of synapses. Our results indicate that hippocampal combinatorial plasticity induced by cellular conditioning paradigm may encode hippocampus dependent learning and memory much better compared with LTP and LTD induced by low frequency stimulation or high frequency stimulation independently and may reflect the flexibility and stability of hippocampal synaptic plasticity.

关 键 词：海马双通路 长时程增强 长时程抑制 

分 类 号：Q42[生物学—神经生物学] R338[生物学—生理学]