NMDA receptor antagonism blocks experience-dependent expansion of hippocampal "place fields"
NMDA receptor antagonism blocks experience-dependent expansion of hippocampal "place fields"
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DOI：
10.1016/s0896-6273(01)00401-9
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发表时间：
2001-08-30
期刊：
影响因子：
16.2
通讯作者：
Barnes, CA
中科院分区：
文献类型：
--
作者：
Ekstrom, AD;Meltzer, J;Barnes, CA
与序列学习理论一致，海马位置表征在重复路线跟随过程中不对称地扩展。这种行为诱导的、经验依赖的神经元可塑性表达被NMDA（R）拮抗剂CPP阻断，这表明它可能是由LTP的时间不对称性和联想特性引起的。然而，NMDA（R）拮抗剂对大鼠穿越海马细胞的“位置场”时，海马细胞放电相相对于θ节律的进行性移位范围没有影响。因此，当位置场通常随着经验而扩大时，激发相位和位置之间的关系就会改变，正如基于突触连接强度不对称性解释“相位旋进”的模型所预测的那样。CPP的这些作用模拟了正常衰老过程中发生的变化，表明老年动物可能出现序列学习缺陷的机制。
In agreement with theories of sequence learning, hippocampal place representations expand asymmetrically during repeated route following. This behaviorally induced, experience-dependent expression of neuronal plasticity was blocked by the NMDA(R) antagonist CPP, suggesting that it may result from the temporal asymmetry and associative properties of LTP. NMDA(R) antagonism, however, had no effect on the range of the progressive shift of firing phase of hippocampal cells, relative to the theta rhythm, as the rat traverses the cell's "place field." Thus, when place fields normally expand with experience, the relationship between firing phase and position is altered, as predicted by models that account for "phase precession" on the basis of asymmetry of synaptic connection strengths. These effects of CPP mimic changes that occur during normal aging, suggesting mechanisms by which sequence learning deficits may arise in aged animals.