Modulation of rabbit aortic Ca(2+)-activated K+ channels by pinacidil, cromakalim, and glibenclamide.
Modulation of rabbit aortic Ca(2+)-activated K+ channels by pinacidil, cromakalim, and glibenclamide.
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吡那地尔、克罗卡林和格列本脲对兔主动脉 Ca(2) 激活的 K 通道的调节。
DOI：
10.1152/ajpcell.1993.264.5.c1119
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
McCullough,JR
中科院分区：
文献类型：
--
作者：
Gelband,GH;McCullough,JR
分离兔主动脉平滑肌微粒体，并将大电导Ca(2+)激活的K+(BK)通道掺入平面脂质双层。单价阳离子的选择性顺序和相对渗透率为：K+(1.0)>；Rb+(0.68)>；NH4+(0.14)>；>；Na+，Cs+(<；0.05)。应用吡那地尔或克罗卡林(0.05-10微米)使超极化方向的开放概率(Po)-电压关系发生改变。匹那地尔和克罗卡林分别为0.96+/-0.04和0.52+/-0.03微米。吡那地尔和克罗卡林均不改变通道的电压敏感性(P0变化11-13 mV/e倍)。在-40 mV时的动力学分析表明，吡那地尔(1微米)将通道停留在长关闭状态的时间从173+/-50毫秒减少到86+/-19毫秒，减少了50%。开放时间常数(20ms)无明显变化。格列本脲(10微米)对BK通道的Po无影响。然而，格列本脲逆转了匹那地尔或克罗卡林引起的BK通道Po的增加。这些数据表明，克罗卡林和吡那地尔均可增加单个兔主动脉大电导钙激活钾通道的开放概率，这种通道调节可能与这些药物的血管松弛特性有关。
Rabbit aortic smooth muscle microsomes were isolated and large-conductance Ca(2+)-activated K+ (BK) channels incorporated into planar lipid bilayers. The selectivity sequence and relative permeability ratios for monovalent cations was K+ (1.0) > Rb+ (0.68) > NH4+ (0.14) >> Na+, Cs+ (< 0.05). Application of pinacidil or cromakalim (0.05-10 microM) shifted the probability of opening (Po)-voltage relationship in the hyperpolarizing direction. The concentrations of pinacidil and cromakalim required to increase Po 50% of the maximum value at -40 mV were 0.96 +/- 0.04 and 0.52 +/- 0.03 microM, respectively. Neither pinacidil nor cromakalim altered the voltage sensitivity of the channel (11-13 mV/e-fold change in Po). Kinetic analysis of data at -40 mV demonstrated that pinacidil (1 microM) decreased the length of time the channel dwelled in its long-closed state by 50% from 173 +/- 50 to 86 +/- 19 ms. No significant change was observed for the open time constant (20 ms). Glibenclamide (10 microM) had no effect on Po of BK channels. However, glibenclamide reversed the pinacidil- or cromakalim-stimulated increase in Po of BK channels. These data suggest that both cromakalim and pinacidil increased the probability of opening of single rabbit aortic large-conductance Ca(2+)-activated K+ channels and that this channel modulation may contribute to the vasorelaxant properties of these drugs.
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Ca2 激活的 K 通道有助于血管肌细胞的静息电位。
DOI：
--
发表时间：
2004
期刊：
Pflügers Archiv
影响因子：
--
作者：
U. Trieschmann;G. Isenberg
通讯作者：
G. Isenberg
DOI：
10.1073/pnas.85.10.3329
发表时间：
1988-05-01
影响因子：
11.1
作者：
GIMENEZGALLEGO, G;NAVIA, MA;GARCIA, ML
通讯作者：
GARCIA, ML
DOI：
10.1016/s0006-291x(86)80374-6
发表时间：
1986-11-26
影响因子：
3.1
作者：
SUGIYAMA, T;YOSHIZUMI, M;YAZAKI, Y
通讯作者：
YAZAKI, Y
来自大脑的电压依赖性钙通道并入平面脂质双层
影响因子：
64.8
作者：
M. Nelson;R. French;B. Krueger
通讯作者：
B. Krueger
两种新型血管扩张药物作用机制的相似之处：吡那地尔和 BRL 34915
影响因子：
3
作者：
N. Cook;U. Quast;R. Hof;Y. Baumlin;C. Pally
通讯作者：
C. Pally