A dihydropyridine-sensitive voltage-dependent calcium channel in the sarcolemmal membrane of crustacean muscle.
A dihydropyridine-sensitive voltage-dependent calcium channel in the sarcolemmal membrane of crustacean muscle.
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DOI：
10.1085/jgp.109.3.313
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发表时间：
1997-03
期刊：
影响因子：
--
通讯作者：
Rathmayer W
中科院分区：
文献类型：
--
作者：
Erxleben C;Rathmayer W
在细胞附着的斑块中，研究了一种海洋甲壳类动物，波罗的海等足动物，肌肉中钙通道的单通道电流。向内的钡电流强烈依赖于电压，通道在细胞的静息膜电位时关闭。在8.2 mV（±2.4,n = 13）退极化下，打开概率（Po）增加了e倍。通道打开主要是短暂的（<0.3 ms），并且均匀分布在100 ms脉冲中。平均准宏观电流表现出快速的激活和失活，并且在100毫秒的测试脉冲中没有失活。同样，通道活动在稳定的去极化保持电位下持续存在。以200 mM Ba2+为载流子时，在+30 ~ +80 mV范围内的平均斜率电导为20 pS（±2.6,n = 12）。钙通道激动剂Bay K8644 （10-100 μM）对肌纤维进行预孵育后，长开口的比例大大增加，而在对照条件下，长开口的比例很少。这些电流的性质类似于通过哺乳动物神经、平滑肌和心肌细胞的l型钙通道的电流。
Single-channel currents through calcium channels in muscle of a marine crustacean, the isopod Idotea baltica, were investigated in cell-attached patches. Inward barium currents were strongly voltage-dependent, and the channels were closed at the cell's resting membrane potential. The open probability (Po) increased e-fold for an 8.2 mV (±2.4, n = 13) depolarization. Channel openings were mainly brief (<0.3 ms) and evenly distributed throughout 100-ms pulses. Averaged, quasimacroscopic currents showed fast activation and deactivation and did not inactivate during 100-ms test pulses. Similarly, channel activity persisted at steadily depolarized holding potentials. With 200 mM Ba2+ as charge carrier, the average slope conductance from the unitary currents between +30 and +80 mV, was 20 pS (±2.6, n = 12). The proportion of long openings, which were very infrequent under control conditions, was greatly increased by preincubation of the muscle fibers with the calcium channel agonist, the dihydropyridine Bay K8644 (10–100 μM). Properties of these currents resemble those through the L-type calcium channels of mammalian nerve, smooth muscle, and cardiac muscle cells.
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影响因子：
4
作者：
GOBLET, C;MOUNIER, Y
通讯作者：
MOUNIER, Y
影响因子：
5.5
作者：
ALMERS, W;FINK, R;PALADE, PT
通讯作者：
PALADE, PT
影响因子：
5.5
作者：
FATT, P;GINSBORG, BL
通讯作者：
GINSBORG, BL
蝎子横纹肌纤维中的收缩激活。依赖电压和外部钙。
影响因子：
3.8
作者：
Gilly, W F;Scheuer, T
通讯作者：
Scheuer, T
DOI：
10.1111/j.1749-6632.1991.tb36478.x
发表时间：
1991-10-14
期刊：
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES-SERIES
影响因子：
--
作者：
ARMSTRONG, DL;ROSSIER, MF;WHITE, RE
通讯作者：
WHITE, RE