Postnatal expression of an apamin-sensitive k(ca) current in vestibular calyx terminals.
Postnatal expression of an apamin-sensitive k(ca) current in vestibular calyx terminals.
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DOI：
10.1007/s00232-011-9400-8
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发表时间：
2011-11
影响因子：
2.4
通讯作者：
Rennie, Katherine J.
中科院分区：
文献类型：
--
作者：
Meredith, Frances L.;Li, Gang Q.;Rennie, Katherine J.
前庭外周的传入神经支配模式很复杂，前庭传入神经的放电规律存在很大差异。花萼纤维终止于 I 型前庭毛细胞，并且具有与支配 II 型毛细胞的布顿纤维不同的发射特性。全细胞膜片钳用于研究可能影响萼末端放电模式的离子电流。前庭神经节细胞中潜在的 K(Ca) 电导已被描述，但它们在传入末梢中的存在以前尚未被研究过。 Apamin 是一种 SK 型钙激活 K+ 通道的选择性阻断剂，在出生后 1 至 50 天期间，在从沙鼠半规管分离的萼传入末梢上进行了测试。降低细胞外钙或应用 apamin (20-500 nM) 可减少电压钳中缓慢激活的外向电流。 Apamin 还降低了全细胞电流钳中超极化后的动作电位 (AHP)，但仅限于出生后前两周后。 K+ 通道表达在出生后第一个月内增加，并且发现 SK 通道有助于 AHP，这可能反过来影响花萼前庭传入神经的放电规律。
Afferent innervation patterns in the vestibular periphery are complex and vestibular afferents show a large variation in their regularity of firing. Calyx fibers terminate on type I vestibular hair cells and have firing characteristics distinct from bouton fibers that innervate type II hair cells. Whole cell patch clamp was used to investigate ionic currents that could influence firing patterns in calyx terminals. Underlying K(Ca) conductances have been described in vestibular ganglion cells, but their presence in afferent terminals has not been investigated previously. Apamin, a selective blocker of SK-type calcium-activated K+ channels, was tested on calyx afferent terminals isolated from gerbil semicircular canals during postnatal days 1 to 50. Lowering extracellular calcium or application of apamin (20–500 nM) reduced slowly activating outward currents in voltage clamp. Apamin also reduced the action potential after-hyperpolarization (AHP) in whole cell current clamp, but only after the first two postnatal weeks. K+ channel expression increased during the first postnatal month and SK channels were found to contribute to the AHP, which may in turn influence discharge regularity in calyx vestibular afferents.
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DOI：
10.1152/ajpregu.00460.2009
发表时间：
2010-02-01
影响因子：
2.8
作者：
Li, Gang Q.;Meredith, Frances L.;Rennie, Katherine J.
通讯作者：
Rennie, Katherine J.
影响因子：
2.5
作者：
FERNANDEZ, C;BAIRD, RA;GOLDBERG, JM
通讯作者：
GOLDBERG, JM
发育中大鼠外耳道 I 型毛细胞和萼传入末梢的 M 型 K+ 电流
影响因子：
5.3
作者：
Hurley, Karen M.;Gaboyard, Sophie;Eatock, Ruth Anne
通讯作者：
Eatock, Ruth Anne
影响因子：
2.5
作者：
Limón, A;Pérez, C;Soto, E
通讯作者：
Soto, E
影响因子：
1.7
作者：
Chabbert, C;Chambard, JM;Desmadryl, G
通讯作者：
Desmadryl, G