Gap junctional communication and connexin43 expression in relation to apoptotic cell death and survival of granulosa cells
Gap junctional communication and connexin43 expression in relation to apoptotic cell death and survival of granulosa cells
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DOI：
10.1369/jhc.3a6227.2004
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发表时间：
2004-09-01
影响因子：
3.2
通讯作者：
D'Herde, K
中科院分区：
文献类型：
--
作者：
Krysko, DV;Mussche, S;D'Herde, K
所有脊椎动物的卵巢卵泡闭锁都是通过颗粒细胞层中启动的细胞凋亡介导的。在这里，我们研究了连接蛋白的表达，细胞偶联和细胞凋亡之间的关系在鸟类颗粒细胞。在四个实验组中，将连接蛋白43（Cx43）的定性和定量免疫细胞化学分析和蛋白质印迹以及缝隙连接的电子显微镜观察结果与通过光漂白后荧光恢复获得的缝隙连接偶联的功能数据进行比较：新鲜分离的颗粒细胞的对照组，24小时无血清培养物作为促排卵条件，另外两组细胞凋亡被激素替代或暴露于升高的细胞外钙抑制。我们的工作表明，颗粒细胞的凋亡诱导伴随着细胞偶联水平的增加，并且用差距连接阻断剂α-大黄酸降低细胞偶联剂量依赖性地抑制凋亡。Cx43表达水平与凋亡指数呈负相关，表明Cx43表达在颗粒细胞存活中起作用。我们的研究支持这一假设，即间隙连接偶联在传播细胞死亡信息中发挥作用，并表明Cx43表达本身在颗粒细胞存活中的作用。
Ovarian follicular atresia in all vertebrates is mediated via apoptosis that is initiated in the granulosa cell layer. Here we investigated the relation between connexin expression, cell coupling, and apoptosis in avian granulosa cells. Results from qualitative and quantitative immunocytochemical analysis and Western blotting of connexin43 (Cx43) and electron microscopic observations of gap junctions were compared with functional data on gap junctional coupling obtained by fluorescence recovery after photobleaching in four experimental groups: a control group of freshly isolated granulosa cells, 24-hr serumfree cultures as the apoptosis-inclucing condition, and two other groups in which apoptosis was inhibited by either hormone substitution or exposure to elevated extracellular calcium. Our work shows that apoptosis induction in granulosa cells is accompanied by an increased level of cell coupling and that decreasing cell coupling with the gap junction blocker a-glycyrrhetinic acid dose-dependently inhibits apoptosis. The level of Cx43 expression was inversely related to the apoptotic index, suggesting that Cx43 expression plays a role in granulosa cell survival. Our study supports the hypothesis that gap junctional coupling plays a role in propagating a cell death message and suggests a role for Cx43 expression per se in granulosa cell survival.