High-fidelity transmission acquired via a developmental decrease in NMDA receptor expression at an auditory synapse
High-fidelity transmission acquired via a developmental decrease in NMDA receptor expression at an auditory synapse
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DOI：
10.1523/jneurosci.21-10-03342.2001
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发表时间：
2001-05-15
影响因子：
5.3
通讯作者：
Takahashi, T
中科院分区：
文献类型：
--
作者：
Futai, K;Okada, M;Takahashi, T
成年动物的中枢听觉中继突触跟随高频输入进行声音定位计算。然而，在未成熟的小鼠，在听觉脑干的Held突触的花萼的传输是不准确的高频输入，因为加起来的慢突触电位成分引起异常放电或阻断的动作电位。随着小鼠的成熟，突触电位变得更短，NMDA受体成分更小更快，从而建立了高频输入的精确一对一传输。通过D（-）2-氨基-5-磷酸戊酸（D-APV）阻断NMDA受体，可以在未成熟小鼠中模拟这种高保真传输的发育获得。此外，出生后第7天（P7）双侧耳蜗消融减弱了NMDA受体表达的发育性下降，并阻止了高保真传输的获得。我们认为，小鼠在P10-P12开始的听觉活动下调突触后NMDA受体的表达，从而有助于高保真突触传递的建立。
Central auditory relay synapses in mature animals follow high-frequency inputs for computation of sound localization. In immature mice, however, transmission at the calyx of Held synapse in auditory brainstem was inaccurate for high-frequency inputs because the summed slow synaptic potential components caused aberrant firings or blocked action potentials. As the mice matured, synaptic potentials became shorter, with smaller and faster NMDA receptor components, thereby establishing the precise one-to-one transmission for high-frequency inputs. Developmental acquisition of this high-fidelity transmission could be mimicked experimentally in immature mice by blocking NMDA receptors with D(-)2-amino-5-phosphonovaleric acid (D-APV). Furthermore, bilateral cochlear ablations at postnatal day 7 (P7) attenuated the developmental decrease of NMDA receptor expression and prevented the acquisition of high-fidelity transmission. We suggest that auditory activity, which begins at P10-P12 in mice, downregulates the expression of postsynaptic NMDA receptors, thereby contributing to the establishment of high-fidelity synaptic transmission.