Voltage‐gated transient outward currents in neurons with different firing patterns in rat superior colliculus
Voltage‐gated transient outward currents in neurons with different firing patterns in rat superior colliculus
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大鼠上丘不同放电模式神经元的电压门控瞬态外向电流
DOI：
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
T. Isa
中科院分区：
文献类型：
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作者：
Yasuhiko Saito;T. Isa
1我们使用全细胞膜片钳技术研究了上级丘中间层（SGI）中具有不同放电模式的神经元（规则发放、快速发放和迟发发放神经元）的瞬时外向电流（TOC）的电生理特性。2失活动力学和标准化幅度的分析表明，常规和快速尖峰神经元中的TOC具有快速失活动力学（衰减时间常数（平均值± s.e.m.））。分别为13.8 ± 1.5和11.4 ± 1.2 ms）和低电流密度（分别为36.6 ± 3.3和32.1 ± 4.9 pA pF−1）。另一方面，晚期尖峰神经元中的TOC显示出广泛的失活动力学（36.7 ± 2.4 ms，范围为11.3至147.8 ms）和电流密度（54.0 ± 2.9 pA pF−1，范围为9.8至131.2 pA pF−1）。3在具有慢时间常数（> 50 ms，II类迟发放神经元）的TOC的规则、快和迟发放神经元中，TOC对4-氨基吡啶（4-AP）敏感，IC 50值分别为2.9、2.4和1.2 mm。在具有快速衰减时间常数的TOC（< 30 ms，I类晚期尖峰神经元）的晚期尖峰神经元中，TOC由至少两种4-AP-敏感组分组成（IC 50值为0.2 μm和3.6 mm）。4个I类迟发神经元显示出对4-AP高度敏感的非失活外向电流。它们将其放电模式改变为常规尖峰模式，不仅响应于低浓度的4-AP（< 50 μm），而且响应于树毒素（200 nm），这表明非失活外向电流有助于晚期尖峰特性。然而，对4-AP高度敏感的TOC组分也对树毒素敏感。这些结果表明，这两种电流的两者或其中之一有助于I类迟发放神经元的迟发放特性。5虽然II类迟峰神经元也显示出非失活外向电流，但迟峰特性并没有被低浓度的4-AP和树毒素消除。它们响应于高浓度的4-AP（5 mm）而改变为规则的放电模式，这表明TOC有助于II类晚期尖峰神经元的晚期尖峰特性。6结果表明，不同性质的TOC对SGI神经元的放电模式有不同的影响。
1 We investigated the electrophysiological properties of transient outward currents (TOCs) in neurons with different firing patterns, regular‐spiking, fast‐spiking and late‐spiking neurons, in the intermediate layer (SGI) of the superior colliculus using the whole‐cell patch clamp technique in slice preparations obtained from young rats (post‐natal days 17–22). 2 Analysis of inactivation kinetics and normalized amplitude revealed that TOCs in regular‐and fast‐spiking neurons had fast inactivation kinetics (decay time constants (mean ± s.e.m.) of 13.8 ± 1.5 and 11.4 ± 1.2 ms, respectively) and low current densities (36.6 ± 3.3 and 32.1 ± 4.9 pA pF−1, respectively). TOCs in late‐spiking neurons, on the other hand, displayed a wide range of both inactivation kinetics (36.7 ± 2.4 ms, with a range from 11.3 to 147.8 ms) and current density (54.0 ± 2.9 pA pF−1, with a range from 9.8 to 131.2 pA pF−1). 3 In regular‐, fast‐ and late‐spiking neurons having TOCs with slow time constants (> 50 ms, class II late‐spiking neurons), the TOCs were sensitive to 4‐aminopyridine (4‐AP), with IC50 values of 2.9, 2.4 and 1.2 mm, respectively. In late‐spiking neurons having TOCs with fast decay time constants (< 30 ms, class I late‐spiking neurons), the TOCs were composed of at least two 4‐AP‐sensitive components (IC50 values of 0.2 μm and 3.6 mm). 4 Class I late‐spiking neurons displayed non‐inactivating outward currents which were highly sensitive to 4‐AP. They changed their firing patterns to the regular‐spiking mode, not only in response to low concentrations of 4‐AP (< 50 μm), but also in response to dendrotoxin (200 nm), suggesting that non‐inactivating outward currents contribute to the late‐spiking property. However, the components of TOCs which were highly sensitive to 4‐AP were also sensitive to dendrotoxin. These results suggest that both or either of the two currents contribute to the late‐spiking property of class I late‐spiking neurons. 5 Although class II late‐spiking neurons also displayed non‐inactivating outward currents, the late‐spiking property was not abolished by low concentrations of 4‐AP and dendrotoxin. They changed to a regular firing pattern in response to a high concentration of 4‐AP (5 mm), suggesting that TOCs contribute to late‐spiking property of class II late‐spiking neurons. 6 The results suggest that TOCs with different properties contribute to the different firing patterns of SGI neurons.
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影响因子：
2.5
作者：
MCCORMICK, DA;CONNORS, BW;PRINCE, DA
通讯作者：
PRINCE, DA
电压门控 K 通道 β 亚基：成年大鼠脑中 Kv β 1 和 Kv β 2 的表达和分布。
DOI：
10.1523/jneurosci.16-16-04846.1996
发表时间：
1996
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience.
影响因子：
--
作者：
Rhodes,KJ;Monaghan,MM;Barrezueta,NX;Nawoschik,S;Bekele-Arcuri,Z;Matos,MF;Nakahira,K;Schechter,LE;Trimmer,JS
通讯作者：
Trimmer,JS
小鼠脑钾通道 beta1 亚基 mRNA：发育过程中的克隆和分布。
DOI：
--
发表时间：
1998
期刊：
Journal of neurobiology.
影响因子：
--
作者：
Butler,DM;Ono,JK;Chang,T;McCaman,RE;Barish,ME
通讯作者：
Barish,ME
影响因子：
2.5
作者：
SERODIO, P;KENTROS, C;RUDY, B
通讯作者：
RUDY, B
影响因子：
2.5
作者：
FOEHRING, RC;SURMEIER, DJ
通讯作者：
SURMEIER, DJ