LOCAL MODULATION OF INTRACELLULAR CALCIUM LEVELS NEAR A SINGLE-CELL WOUND IN HUMAN ENDOTHELIAL MONOLAYERS
LOCAL MODULATION OF INTRACELLULAR CALCIUM LEVELS NEAR A SINGLE-CELL WOUND IN HUMAN ENDOTHELIAL MONOLAYERS
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DOI：
10.1161/01.atv.11.5.1258
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发表时间：
1991-09-01
期刊：
影响因子：
--
通讯作者：
HUBBELL, JA
中科院分区：
文献类型：
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作者：
DRUMHELLER, PD;HUBBELL, JA
使用具有单个机械裂解细胞的内皮细胞单层作为模型来检查伤口附近局部钙动员的程度、动力学和性质。 来自汇合单层的单个内皮细胞用与显微操作器偶联的细针机械裂解，同时对相邻细胞没有产生可观察到的机械创伤。 用钙敏感荧光团indo-1通过落射荧光显微光度法监测伤口部位周围单个细胞中钙水平的变化。 邻近伤口部位的单个细胞显示其细胞内钙水平大幅增加，几乎与离子载体对照获得的钙水平一样高。 细胞内钙动员的汇合单层的幅度随着距离伤口部位的距离而降低，并且位于距离伤口部位大于7个细胞的半径处的那些细胞的钙水平没有变化。 因此，单个细胞的裂解导致约200个相邻细胞中的钙动员。 细胞内钙达到最大水平所需的时间也随着距离伤口部位的距离而增加。 钙动员部分是细胞内，并通过破坏细胞-细胞偶联或通过庚醇增加间隙连接阻力来抑制。 这种动员在亚融合内皮单层中大大减弱，在成纤维细胞或平滑肌细胞中未观察到;此外，在故意污染平滑肌细胞的单层中，这种作用是有缺陷的。 本研究探讨了显微镜下内皮损伤附近局部内皮激活的程度和可能的机制。
An endothelial cell monolayer with a single mechanically lysed cell was used as a model to examine the extent, kinetics, and nature of local calcium mobilization in the neighborhood of a wound. Individual endothelial cells from confluent monolayers were mechanically lysed with a minutien needle coupled to a micromanipulator while producing no observable mechanical trauma to the neighboring cells. Changes in calcium levels in individual cells surrounding the wound site were monitored by epifluorescence microphotometry with the calcium-sensitive fluorophore indo-1. Individual cells adjacent to the wound site showed a substantial increase in their intracellular calcium levels, almost as high as the calcium levels attained by ionophore controls. The magnitude of intracellular calcium mobilization in confluent monolayers decreased with distance from the wound site, and those cells located at a radius greater than seven cells from the wound site showed no change in their calcium levels. Thus, lysis of a single cell resulted in calcium mobilization in approximately 200 neighboring cells. The time necessary for intracellular calcium to reach maximum levels also increased with distance from the wound site. Calcium mobilization was partly intracellular and was inhibited by disrupting cell-cell coupling or by increasing gap junction resistance by heptanol. This mobilization was greatly attenuated in subconfluent endothelial monolayers, and it was not observed in fibroblasts or smooth muscle cells; furthermore, the effect was defective in monolayers intentionally contaminated with smooth muscle cells. This study examines the extent and possible mechanisms of local endothelial activation near a microscopic endothelial wound.