ACTIVITY-DEPENDENT DECREASE IN NMDA RECEPTOR RESPONSES DURING DEVELOPMENT OF THE VISUAL-CORTEX
ACTIVITY-DEPENDENT DECREASE IN NMDA RECEPTOR RESPONSES DURING DEVELOPMENT OF THE VISUAL-CORTEX
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DOI：
10.1126/science.1279803
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发表时间：
1992-11-06
期刊：
影响因子：
56.9
通讯作者：
VICINI, S
中科院分区：
文献类型：
--
作者：
CARMIGNOTO, G;VICINI, S
发育中的视觉系统的可塑性被认为是研究环境影响下神经元连接变化的最佳模型。N-甲基-D-天冬氨酸（NMDA）受体对发育中的视皮层中发生的经验依赖性突触修饰至关重要。NMDA介导的兴奋性突触后电流（EPSC）在第IV层神经元的视皮层持续时间较长的年轻大鼠比成年大鼠，和EPSC的持续时间变得越来越短，在平行的突触可塑性的发展减少。当动物在黑暗中饲养时，这种NMDA受体介导的EPSC持续时间的减少被延迟，这是一种破坏发育可塑性的条件，并且可以通过用河豚毒素治疗来防止，这是一种抑制神经活动的方法。应用L-谷氨酸外向补丁切除的第四层神经元的年轻，但不是成年，大鼠激活长期爆发的NMDA通道开放。因此，NMDA受体门控特性的改变可能是视觉皮层可塑性随年龄增长而下降的原因。
Plasticity of the developing visual system has been regarded as the best model for changes of neuronal connections under the influence of the environment. N-methyl-D-aspartate (NMDA) receptors are crucial for experience-dependent synaptic modifications that occur in the developing visual cortex. NMDA-mediated excitatory postsynaptic currents (EPSCs) in layer IV neurons of the visual cortex lasted longer in young rats than in adult rats, and the duration of the EPSCs became progressively shorter, in parallel with the developmental reduction in synaptic plasticity. This decrease in NMDA receptor-mediated EPSC duration is delayed when the animals are reared in the dark, a condition that prolongs developmental plasticity, and is prevented by treatment with tetrodotoxin, a procedure that inhibits neural activity. Application of L-glutamate to outside-out patches excised from layer IV neurons of young, but not of adult, rats activated prolonged bursts of NMDA channel openings. A modification of the NMDA receptor gating properties may therefore account for the age-dependent decline of visual cortical plasticity.