Dye spread through gap junctions in the corneal epithelium of the rabbit.
Dye spread through gap junctions in the corneal epithelium of the rabbit.
复制标题
染料通过兔子角膜上皮的间隙连接扩散。
DOI：
10.1076/ceyr.16.5.445.7039
复制
发表时间：
1997
影响因子：
2
通讯作者：
Watsky,MA
中科院分区：
文献类型：
--
作者：
Williams,KK;Watsky,MA
目的使用微电极染料注射5,6-羧基荧光素来研究角膜上皮中的间隙连接通讯。方法染料注射从表层开始，逐步进入下面的上皮层，直到观察到扩散。通过将角膜暴露于钙离子载体A23187（整体增加）或通过增加注射电极中的[Ca 2+ ]（源细胞增加）来操纵细胞内[Ca 2+ ]。通过将角膜暴露于低 pH 值 KCl 林格氏液中的尼日利亚菌素（整体降低）或降低注射电极的 pH 值（源细胞降低）来控制细胞内 pH 值。测试了庚醇解偶联间隙连接的能力。间隙连接通讯基于首先观察到扩散的层以及距注射点的表观染料行进距离。结果平均而言，控制染料扩散发生在距离表面的第三层。源细胞中 [Ca 2+ ] 的增加导致第二层发生初始扩散。使用 A23187 整体增加 [Ca 2+ ] 不会导致平均初始扩散层发生变化。降低源细胞的细胞内 pH 值不会影响初始染料铺展层。整体降低细胞内 pH 值导致间隙连接以时间依赖性方式受到显着抑制。染料扩散距离不受 [Ca 2+ ] 或 pH 控制的显着影响。庚醇 (2.5 mM) 完全抑制染料耦合。 结论 角膜上皮的所有细胞层都含有功能性间隙连接，尽管在我们的控制条件下似乎不发生浅层细胞间通讯。通过这些连接的细胞间通讯可以通过 [Ca 2+ ] 和 pH 的各种操作来改变。
PURPOSEMicroelectrode dye injection of 5,6-carboxyfluores-cein was used to investigate gap junctional communication in the corneal epithelium.METHODSDye injection started in the superficial layer and pro-ceeded stepwise into the underlying epithelial layers until spread was observed. Intracellular [Ca 2+ ] was manipulated by exposing the cornea to the calcium ionophore A23187 (global increase) or by increasing the [Ca 2+ ] in the injection electrode (source cell increase). Intracellular pH was manipulated by exposing the cornea to nigericin in a low-pH KCl Ringer's (global decrease) or by lowering the pH in the injection elec-trode (source cell decrease). Heptanol was tested for its ability to uncouple gap junctions. Gap junctional communication was based on the layer at which spread was first observed and on the apparent dye travel distance from the point of injection.RESULTSControl dye spread occurred, on average, in the third layer from the surface. Increased [Ca 2+ ] in the source cell resulted in an initial spread occurring in the second layer. Globally increasing [Ca 2+ ] with A23187 resulted in no change in the average initial spread layer. Lowering intracellular pH of the source cell did not affect the initial dye spread layer. Globally lowering intracellular pH resulted in significant gap junctional inhibition in a time-dependent manner. Dye spread distance was not significantly affected by [Ca 2+ ] or pH manipu-lations. Heptanol (2.5 mM) completely inhibited dye coupling.CONCLUSIONAll cell layers of the corneal epithelium contain functional gap junctions, although it appears that intercellular communication in the superficial layers does not occur under our control conditions. Intercellular communication through these junctions can be altered by various manipulations of [Ca 2+ ] and pH.