Role of T-type calcium current in identified D-hair mechanoreceptor neurons studied in vitro
Role of T-type calcium current in identified D-hair mechanoreceptor neurons studied in vitro
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DOI：
10.1523/jneurosci.1598-04.2004
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发表时间：
2004-09-29
影响因子：
5.3
通讯作者：
Scamps, F
中科院分区：
文献类型：
--
作者：
Dubreuil, AS;Boukhaddaoui, H;Scamps, F
Different subsets of dorsal root ganglion (DRG) mechanoreceptors transduce low- and high-intensity mechanical stimuli. It was shown recently that, in vivo, neurotrophin-4 (NT-4)-dependent D-hair mechanoreceptors specifically express a voltage-activated T-type calcium channel (Ca(v)3.2) that may be required for their mechanoreceptive function. Here we show that D-hair mechanoreceptors can be identified in vitro by a rosette-like morphology in the presence of NT-4 and that these rosette neurons are almost all absent in DRG cultures taken from NT-4 knock-out mice. In vitro identification of the D-hair mechanoreceptor allowed us to explore the electrophysiological properties of these cells. We demonstrate that the T-type Ca(v)3.2 channel induced slow membrane depolarization that contributes to lower the voltage threshold for action potential generation and controls spike latency after stimulation of D-hair mechanoreceptors. Indeed, the properties of the T-type amplifier are particularly well suited to explain the high sensitivity of D-hair mechanoreceptors to slowly moving stimuli.
