Zahs K R
Department of Physiology, School of Medicine, University of Minnesota, Minneapolis 55455, USA.
Glia. 1998 Sep;24(1):85-96.
Heterotypic coupling, defined as gap-junctional coupling between cells of different classes, may be common among the different types of non-neuronal cells in the central nervous system. Since gap junctions provide a route for the intercellular exchange of signaling molecules, heterotypic coupling may serve to coordinate the activities of many types of "support cells" in the brain. The evidence for heterotypic coupling between astrocytes and oligodendrocytes, astrocytes and retinal Müller glial cells, and astrocytes and ependymal cells is reviewed. The finding that some heterotypic gap junctions are chemically rectifying implies that there is asymmetry between the two sides of these gap junctions, and the connexin composition of heterotypic gap junctions is discussed. Finally, I speculate about the functions of heterotypic gap junctions, including their proposed roles in K+ spatial buffering around axons and in the propagation of intercellular Ca2+ waves between astrocytes and other glial cells.
异型耦联被定义为不同类型细胞之间的缝隙连接耦联，在中枢神经系统的不同类型非神经元细胞中可能很常见。由于缝隙连接为信号分子的细胞间交换提供了一条途径，异型耦联可能有助于协调大脑中多种类型“支持细胞”的活动。本文综述了星形胶质细胞与少突胶质细胞、星形胶质细胞与视网膜Müller胶质细胞以及星形胶质细胞与室管膜细胞之间异型耦联的证据。一些异型缝隙连接具有化学整流作用这一发现意味着这些缝隙连接两侧存在不对称性，并对异型缝隙连接的连接蛋白组成进行了讨论。最后，我推测了异型缝隙连接的功能，包括它们在轴突周围K+空间缓冲以及星形胶质细胞与其他胶质细胞之间细胞间Ca2+波传播中所提出的作用。
