Evidence for nicotinic acetylcholine receptor activation in rat cerebellar slices
Evidence for nicotinic acetylcholine receptor activation in rat cerebellar slices
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DOI：
10.1016/s0091-3057(01)00653-0
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发表时间：
2001-12-01
影响因子：
3.6
通讯作者：
Sher, E
中科院分区：
文献类型：
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作者：
De Filippi, G;Baldwinson, T;Sher, E
已知神经元烟碱型ACh受体（nAChR）激活可增强不同脑区中谷氨酸和GABA的释放。此外，nAChR在神经元分化中起重要作用。应用膜片钳技术，我们研究了P5-P14大鼠小脑颗粒细胞切片中nAChRs的存在。ACh（1 mM）的应用可引起多种效应。有些细胞根本没有反应。在其他细胞中，体细胞电流被激活。在一定比例的细胞，突触后电流（PSC），或没有体细胞电流，引起。体细胞nAChR可能是α 4 β 2亚型，但不能排除其他亚基组合（含α 7或β 4受体）的存在。ACh诱导的PSC本质上是谷氨酸能的。因此，在合理比例的细胞中，烟碱受体存在于突触前。它们可能是α（7）受体，其激活通过TTX敏感机制促进Glu释放。我们的实验是第一个电生理证据显示，在一个本地小脑制备，烟碱受体的存在下，苔藓纤维颗粒细胞突触在早期发育阶段。(C)2001 Elsevier Science Inc. All rights reserved.
Neuronal nicotinic ACh receptor (nAChR) activation is known to enhance glutamate and GABA release in different brain areas. Moreover, nAChRs play an important role in neuronal differentiation. By using the patch-clamp technique, we have investigated the presence of nAChRs in cerebellar granule cells in slices from P5-P14 rats. Application of ACh (1 mM) could elicit a variety of effects. Some cells did not respond at all. In other cells, a somatic current was activated. In a proportion of cells, postsynaptic currents (PSCs), with or without somatic current, were elicited. Somatic nAChRs are likely to be of the alpha(4)beta(2) subtype, but the presence of other subunit combinations (alpha(7)- or beta(4)-containing receptors) cannot be ruled out. The ACh-induced PSCs were glutamatergic in nature. Thus, in a reasonable proportion of cells, nicotinic receptors are present presynaptically. They are likely to be alpha(7) receptors whose activation elicits Glu release via a TTX-sensitive mechanism. Our experiments are the first electrophysiological evidence showing, in a native cerebellar preparation, the presence of nicotinic receptors at the mossy fibre-granule cell synapse at early developmental stages. (C) 2001 Elsevier Science Inc. All rights reserved.