Electrophysiological properties of gap junctions between dissociated pairs of rat hepatocytes.
Electrophysiological properties of gap junctions between dissociated pairs of rat hepatocytes.
复制标题
DOI：
10.1083/jcb.103.1.135
复制
发表时间：
1986-07
影响因子：
7.8
通讯作者：
ARIAS, IM
中科院分区：
文献类型：
--
作者：
SPRAY, DC;GINZBERG, RD;MORALES, EA;GATMAITAN, Z;ARIAS, IM
分离的大鼠肝细胞对的生理特性进行了检查后5小时内解离。这些细胞在分离时变圆，但细胞对仍然显示膜特化。最值得注意的是，小管通常存在于并置膜，其两侧是丰富的间隙和紧密连接。这些细胞对是强染料耦合的;荧光黄CH注入一个细胞迅速扩散到另一个细胞。成对的肝细胞是紧密电耦合的。连接膜的电导对电压不敏感：电压钳研究表明，gj对任一极性的长（5 s）跨接电压阶跃（从静止到大于+/- 40 mV）的响应是恒定的。接触辛醇（0.1 mM）和细胞内酸化可降低肝细胞对之间的连接电导（gj）。用液体离子交换微电极测量的正常细胞内pH（pHi）通常为7.1-7.4，用100%CO2平衡的盐水灌注将pHi降低至6.0- 6.5。在7.5-6.6的pHi范围内，gj是恒定的。低于pH 6.6时，gj急剧下降，在6.1时偶联检测不到。当用生理盐水冲洗细胞时，pHi恢复;在大多数情况下，gj平行恢复，使得酸化或恢复期间获得的pH的gj值相似。肝脏间隙连接的低表观pK和非常陡峭的pHi-gj关系与其他组织中较高的pK和逐渐上升的曲线形成对比。如果H+离子直接作用于连接分子，那么在不同组织中可能同源的通道必须在反应位点或其环境方面有所不同。
Physiological properties of isolated pairs of rat hepatocytes were examined within 5 h after dissociation. These cells become round when separated, but cell pairs still display membrane specializations. Most notably, canaliculi are often present at appositional membranes which are flanked by abundant gap and tight junctions. These cell pairs are strongly dye-coupled; Lucifer Yellow CH injected into one cell rapidly diffuses to the other. Pairs of hepatocytes are closely coupled electrically. Conductance of the junctional membrane is not voltage sensitive: voltage clamp studies demonstrate that gj is constant in response to long (5 s) transjunctional voltage steps of either polarity (to greater than +/- 40 mV from rest). Junctional conductance (gj) between hepatocyte pairs is reduced by exposure to octanol (0.1 mM) and by intracellular acidification. Normal intracellular pH (pHi), measured with a liquid ion exchange microelectrode, was generally 7.1-7.4, and superfusion with saline equilibrated with 100% CO2 reduced pHi to 6.0- 6.5. In the pHi range 7.5-6.6, gj was constant. Below pH 6.6, gj steeply decreased and at 6.1 coupling was undetectable. pHi recovered when cells were rinsed with normal saline; in most cases gj recovered in parallel so that gj values were similar for pHs obtained during acidification or recovery. The low apparent pK and very steep pHi-gj relation of the liver gap junction contrast with higher pKs and more gradually rising curves in other tissues. If H+ ions act directly on the junctional molecules, the channels that are presumably homologous in different tissues must differ with respect to reactive sites or their environment.
登录
查看更多内容
影响因子：
2.4
作者：
GIRSCH, SJ;PERACCHIA, C
通讯作者：
PERACCHIA, C
影响因子：
7.8
作者：
SCHUETZE, SM;GOODENOUGH, DA
通讯作者：
GOODENOUGH, DA
DOI：
10.1073/pnas.82.8.2412
发表时间：
1985-01-01
影响因子：
11.1
作者：
HERTZBERG, EL;SPRAY, DC;BENNETT, MVL
通讯作者：
BENNETT, MVL
小鼠心脏和肝脏的细胞间连接处的亚基的六边形阵列。
影响因子：
7.8
作者：
Revel, J P;Karnovsky, M J
通讯作者：
Karnovsky, M J
影响因子：
64.8
作者：
ROSE, B;LOEWENSTEIN, WR
通讯作者：
LOEWENSTEIN, WR