Passive properties of the membrane of single freshly isolated smooth muscle cells.
Passive properties of the membrane of single freshly isolated smooth muscle cells.
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单个新鲜分离的平滑肌细胞膜的被动特性。
DOI：
10.1152/ajpcell.1980.239.5.c153
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
WalshJr,JV
中科院分区：
文献类型：
--
作者：
Singer,JJ;WalshJr,JV
从蟾蜍的胃肌层分离单个平滑肌细胞，并在分离的同一天使用标准电生理技术和直接显微镜观察在高放大倍数下进行研究。渗透后发生一段时间的超极化，似乎是由增加K+电导激活的Ca 2+进入细胞后渗透。离子替代研究表明，稳定的稳态静息电位依赖于[Na+]0和[K+]0。当[Ca ~（2+）]_0 = 1.8mM时，可诱发主动反应，而当[Ca ~（2+）]_0较高时（<8 mM），则可诱发具有过冲的动作电位。计算采用的方程为短电缆和观察到的变化膜电位作为一个单一的指数响应于一个小的超极化电流步骤都表明，长度常数（λ）是足够大于细胞长度，使细胞表现为一个等电位面在亚阈值扰动。从所研究的每个电池的显微照片测量和输入电阻，获得了比膜电阻（Rm）的值，其范围高达152 k Ω x cm 2，这取决于离子环境，最显著地取决于[Ca 2 +]0。膜容量（Cm）是指用光学显微镜测量的表面积，为1.3 +/- 0.3 microF/cm 2（平均值+/- SD）。当包括小窝膜面积的最佳估计时，Cm指的是总膜面积（小窝加非小窝）约为0.8 microF/cm 2。
Single, smooth muscle cells were isolated from the stomach muscularis of the toad Bufo marinus and studied on the same day as isolation using standard electrophysiological techniques and direct microscopic observation at high magnification. Following penetration a period of hyperpolarization occurred that appeared to be caused by an increase in K+ conductance activated by Ca2+ entering the cell upon penetration. Ion substitution studies showed that the stable steady-state resting potential was dependent on both [Na+]0 and [K+]0. At [Ca2+]0 = 1.8 mM, active responses could be elicited which, at the higher [Ca2+]0 (< 8mM) generally employed, became action potentials with overshoots. Calculations employing the equations for a short cable and the observed change of membrane potential as a single exponential in response to a small hyperpolarizing current step both indicated that the length constant (lambda) was sufficiently greater than the cell length so that the cell behaved as an isopotential surface during subthreshold perturbations. From photomicrographic measurements of each cell studied and the input resistance, values of specific membrane resistance (Rm) were obtained that ranged as high as 152 k omega x cm2 depending on the ionic environment, most notably on [Ca2+]0. The membrane capacity (Cm) referred to the surface area measured with light microscopy was 1.3 +/- 0.3 microF/cm2 (mean +/- SD). When the best estimate of caveolar membrane area was included, Cm referred to total membrane area (caveolar plus noncaveolar) was approximately 0.8 microF/cm2.
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吖啶橙与 RNA 的固体复合物的发光。
DOI：
10.1002/cyto.990020402
发表时间：
1982
期刊：
Cytometry
影响因子：
--
作者：
Kapuscinski,J;Darzynkiewicz,Z;Melamed,MR
通讯作者：
Melamed,MR
组蛋白与脱氧核糖核酸关联的特异性。
影响因子：
2.9
作者：
A. Ansevin;B. W. Brown
通讯作者：
B. W. Brown
核基质：核内蛋白质磷酸化增加的细胞周期依赖性位点。
DOI：
--
发表时间：
1983
期刊：
European Journal of Biochemistry
影响因子：
--
作者：
Sally M. Henry;Lon D. Hodge
通讯作者：
Lon D. Hodge
影响因子：
5.6
作者：
J. A. Subirana
通讯作者：
J. A. Subirana
组织特异性组蛋白与脱氧核糖核酸的关联。
DOI：
--
发表时间：
1975
期刊：
影响因子：
--
作者：
Tsai Yh;Ansevin At;Hnilica Ls
通讯作者：
Hnilica Ls