On-line analysis of gap junctions reveals more efficient electrical than dye coupling between islet cells.
On-line analysis of gap junctions reveals more efficient electrical than dye coupling between islet cells.
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间隙连接的在线分析揭示了胰岛细胞之间的电耦合比染料耦合更有效。
DOI：
10.1152/ajpendo.00473.2002
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Soria,Bernat
中科院分区：
文献类型：
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作者：
Quesada,Ivan;Fuentes,Esther;Andreu,Etelvina;Meda,Paolo;Nadal,Angel;Soria,Bernat
胰腺β细胞构成了一个沟通良好的多细胞网络，允许在郎格汉斯胰岛内进行协调和同步的信号传输，这是正确释放胰岛素所必需的。缝隙连接是调节细胞功能连接的分子钥匙，在大多数细胞类型中负责电和代谢耦合。虽然缝隙连接在β-细胞电耦合中的作用已经被很好地记录下来，但代谢通讯仍然是一个讨论的问题。在这里，我们通过使用光漂白后荧光恢复(FRAP)的方法来解决这个问题。这项技术已经被证实是一种可靠的、非侵入性的实时监测功能缝隙连接的方法。我们发现，在允许携带电流离子的细胞间交换的条件下，对照胰岛细胞不会在聚集的细胞或完整的朗格汉斯胰岛中交换缝隙连接分子。相反，我们检测到相同的探针在表达连接蛋白32(Cx32)的转基因小鼠的胰岛细胞之间广泛转移，这些转基因小鼠具有增强的连接偶联特性。结果表明，天然胰岛细胞的电耦合比染料通讯更为广泛。胰岛细胞中的染料偶联结构域似乎比以前用其他方法推断的更受限制。
Pancreatic β-cells constitute a well-communicating multicellular network that permits a coordinated and synchronized signal transmission within the islet of Langerhans that is necessary for proper insulin release. Gap junctions are the molecular keys that mediate functional cellular connections, which are responsible for electrical and metabolic coupling in the majority of cell types. Although the role of gap junctions in β-cell electrical coupling is well documented, metabolic communication is still a matter of discussion. Here, we have addressed this issue by use of a fluorescence recovery after photobleaching (FRAP) approach. This technique has been validated as a reliable and noninvasive approach to monitor functional gap junctions in real time. We show that control pancreatic islet cells did not exchange a gap junction-permeant molecule in either clustered cells or intact islets of Langerhans under conditions that allowed cell-to-cell exchange of current-carrying ions. Conversely, we have detected that the same probe was extensively transferred between islet cells of transgenic mice expressing connexin 32 (Cx32) that have enhanced junctional coupling properties. The results indicate that the electrical coupling of native islet cells is more extensive than dye communication. Dye-coupling domains in islet cells appear more restricted than previously inferred with other methods.