期刊
NATURE
卷 430, 期 7001, 页码 790-793出版社
NATURE PUBLISHING GROUP
DOI: 10.1038/nature02775
关键词
-
资金
- NIDA NIH HHS [F32 DA015164] Funding Source: Medline
At central excitatory synapses, N-methyl-D-aspartate (NMDA) receptors, which have a high affinity for glutamate(1), produce a slowly rising synaptic current in response to a single transmitter pulse and an additional current after a second, closely timed stimulus(2). Here we show, by examining the kinetics of transmitter binding and channel gating in single-channel currents from recombinant NR1/NR2A receptors, that the synaptic response to trains of impulses is determined by the molecular reaction mechanism of the receptor. The rate constants estimated for the activation reaction predict that, after binding neurotransmitter, receptors hesitate for similar to4 ms in a closed high-affinity conformation before they either proceed towards opening or release neurotransmitter, with about equal probabilities. Because only about half of the initially fully occupied receptors become active, repetitive stimulation elicits currents with distinct waveforms depending on pulse frequency. This high-affinity/low-efficiency activation mechanism might serve as a link between stimulation frequency and the directionality of the ensuing synaptic plasticity.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据