Fractional Ca2+ current through human neuronal α7 nicotinic acetylcholine receptors
Fractional Ca2+ current through human neuronal α7 nicotinic acetylcholine receptors
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DOI：
10.1016/s0143-4160(03)00071-x
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发表时间：
2003-08-01
期刊：
影响因子：
4
通讯作者：
Eusebi, F
中科院分区：
文献类型：
--
作者：
Fucile, S;Renzi, M;Eusebi, F
神经元α 7烟碱乙酰胆碱（ACh）受体被认为是高度Ca 2+渗透的配体门控受体通道。然而，迄今尚未直接测量到Ca 2+对ACh产生的阳离子电流的贡献。在稳定表达人α 7受体的GH4 C1垂体细胞中，使用Ca 2+指示剂染料Fura-2同时进行荧光和全细胞电流测量，并测定部分Ca 2+电流（由Ca 2+携带的全细胞电流的比例; P-f）。我们报告P-f值为11.4 +/-1.3%。该值显著大于在瞬时转染的GH4 C1细胞中测定的人L248 α 7受体突变体的P-f（P-f = 6.3 +/- 1.0%）和大鼠α 7受体的P-f（P-f = 8.8 +/- 1.5%）。据我们所知，本文报道的研究结果表明，人α 7受体是在异源细胞系统中表达的最具Ca 2+传导性的同源配体门控受体通道。(C)2003爱思唯尔科技有限公司版权所有。
The neuronal alpha7 nicotinic acetylcholine (ACh) receptor is believed to be a highly Ca2+ permeable ligand-gated receptor-channel. However, the contribution of Ca2+ to cationic current generated by ACh has not yet been directly measured to date. Simultaneous fluorescence and whole-cell current measurements using the Ca2+ indicator dye fura-2 were made in GH4C1 pituitary cells stably expressing human alpha7 receptors and the fractional Ca2+ current (the proportion of whole-cell current carried by Ca2+; P-f) was determined. We report that the P-f value was 11.4 +/- 1.3%. This value was significantly larger than P-f of human L248Talpha7 receptor mutant (P-f = 6.3 +/- 1.0%) and of rat alpha7 receptor (P-f = 8.8 +/- 1.5%) both determined in transiently transfected GH4C1 cells. In our knowledge, the findings here reported indicate the human alpha7 receptors are the most Ca2+ conductive homomeric ligand-gated receptor-channels expressed in a heterologous cell system. (C) 2003 Elsevier Science Ltd. All rights reserved.