Multiple kinetic states underlying macroscopic M-currents in bullfrog sympathetic neurons
Multiple kinetic states underlying macroscopic M-currents in bullfrog sympathetic neurons
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牛蛙交感神经元宏观 M 电流的多种动力学状态
DOI：
10.1098/rspb.1992.0063
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
W. Gruner
中科院分区：
文献类型：
--
作者：
N. Marrion;P. Adams;W. Gruner
M电流是一种时间和电压依赖性钾电流，可被毒蕈碱受体激活抑制。我们已经使用曲线拟合和噪声分析，以确定宏观M-电流是否偏离先前预测的简单的两态动力学方案。M-电流最好用三个动力学上不同的组分来描述：“快”（100）、“中间”（101）和“慢”（102）时间常数。从M-电流噪声的频谱中识别出“快”（α 0）和“中间”（α 1）成分，其电位与细胞的静息膜电位正相关。通过曲线拟合M-电流失活电流，观察到“中间”（α 1）和“慢”（α 2）分量。“中间”（α 1）时间常数是电压依赖性的（在23 mV时减小e倍），但“快”（α 0）和“慢”（α 2）组分的电压依赖性不明显。所有的动力学成分都对毒蕈碱敏感，其中“中间”（101）和“慢”（102）同样如此。这些数据表明，所有组件可能来自相同的通道人口，和M-通道可能有至少四个动力学状态。
M-current is a time- and voltage-dependent potassium current which is suppressible by muscarinic receptor activation. We have used curve fitting and noise analysis to determine if macroscopic M-currents deviate from a previously predicted simple two-state kinetic scheme. The M-current was best described by three kinetically distinct components: 'fast' (⊤0), ‘intermediate’ (⊤1) and ‘slow’ (⊤2) time constants. The ‘fast’ (⊤0) and ‘intermediate’ (⊤1) components were identified from the spectra of M-current noise at potentials positive to the cells’ resting membrane potential. The ‘intermediate’ (⊤1) and ‘slow’ (⊤2) components were seen by curve fitting M-current deactivation currents. The ‘intermediate’ (⊤1) time constant was voltage dependent (decreasing e-fold in 23 mV), but voltage dependence of the ‘fast’ (⊤0) and ‘slow ’ (⊤2) components was not obvious. All kinetic components were sensitive to muscarine, with the ‘intermediate’ (⊤1) and ‘slow’ (⊤2) being equally so. These data suggest that all components may derive from the same channel population, and that the M-channel may have at least four kinetic states.
DOI：
10.1073/pnas.88.2.652
发表时间：
1991-01-01
影响因子：
11.1
作者：
BEECH, DJ;BERNHEIM, L;HILLE, B
通讯作者：
HILLE, B