Evidence for electrical synapses between neurons of the nucleus reticularis thalami in the adult brain in vitro.
Evidence for electrical synapses between neurons of the nucleus reticularis thalami in the adult brain in vitro.
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DOI：
10.1017/s1472928807000325
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发表时间：
2008-03
期刊：
影响因子：
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通讯作者：
Crunelli, Vincenzo
中科院分区：
文献类型：
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作者：
Blethyn, Kate L;Hughes, Stuart W;Crunelli, Vincenzo
幼鼠丘脑网状核（NRT）的抑制性神经元通过连接蛋白36 （Cx36）的电突触相互沟通。然而，功能性电突触是否会持续到成年还不完全清楚。本研究表明，在代谢性谷氨酸受体（mGluR）激动剂、反式acpd （100 μM）或DHPG （100 μM）存在的情况下，体外维持的成年猫NRT细胞中15%的神经元表现出典型的小穗，这些小穗具有几种特性，表明它们反映了通过电突触传递的动作电位。特别是，这些小穗，1)显示出一个保守的全有或无的波形，具有明显的后超极化（AHP）， 2)显示出不受膜电位变化影响的振幅和峰值时间，3)总是有节奏地发生，精确的频率随着去极化而增加，4)抵抗传统的快速化学突触传递阻滞剂。因此，这些结果表明，NRT中的功能性电突触持续存在到成年期，它们可能作为一种有效的同步机制，为该核显示的各种生理和病理节律活动提供支持。
It has been conclusively demonstrated in juvenile rodents that the inhibitory neurons of the nucleus reticularis thalami (NRT) communicate with each other via connexin 36 (Cx36)-based electrical synapses. However, whether functional electrical synapses persist into adulthood is not fully known. Here we show that in the presence of the metabotropic glutamate receptor (mGluR) agonists, trans-ACPD (100 μM) or DHPG (100 μM), 15% of neurons in slices of the adult cat NRT maintained in vitro exhibit stereotypical spikelets with several properties that indicate that they reflect action potentials that have been communicated through an electrical synapse. In particular, these spikelets, i) display a conserved all-or-nothing waveform with a pronounced after-hyperpolarization (AHP), ii) exhibit an amplitude and time to peak that are unaffected by changes in membrane potential, iii) always occur rhythmically with the precise frequency increasing with depolarization, and iv) are resistant to blockers of conventional, fast chemical synaptic transmission. Thus, these results indicate that functional electrical synapses in the NRT persist into adulthood where they are likely to serve as an effective synchronizing mechanism for the wide variety of physiological and pathological rhythmic activities displayed by this nucleus.