Giaume C
INSERM U114, Collège de France, Paris.
Ann Endocrinol (Paris). 1996;57(6):487-91.
In the brain, in vivo as in vitro, glial cells represent the main cell population which communicates through intercellular channels forming gap junctions. These cells, and specially the astrocytes, also express a large variety of ionic channels and membrane receptors. The combination of biochemical, immunological and electrophysiological techniques has allowed to determine that connexin 32 is present in oligodendrocytes while connexin 43 is the major junctional protein in astrocytes. The conductance and permeability of gap junctions in astrocytes are controlled by endogenous compounds released from neurons or endothelial cells. This suggests that gap junctional communication in astrocyte networks exhibits some degree of plasticity and are under the control of other brain cell populations. The expression of connexins and the regulation of junctional permeability in astrocytes may contribute to several glial functions such as intercellular calcium signalling and metabolic trafficking within the brain.
在大脑中，如同在体外一样，神经胶质细胞是通过形成缝隙连接的细胞间通道进行通讯的主要细胞群体。这些细胞，特别是星形胶质细胞，还表达多种离子通道和膜受体。生化、免疫和电生理技术的结合已确定连接蛋白32存在于少突胶质细胞中，而连接蛋白43是星形胶质细胞中的主要连接蛋白。星形胶质细胞中缝隙连接的电导和通透性受神经元或内皮细胞释放的内源性化合物控制。这表明星形胶质细胞网络中的缝隙连接通讯表现出一定程度的可塑性，并受其他脑细胞群体的控制。连接蛋白的表达和星形胶质细胞中连接通透性的调节可能有助于多种神经胶质功能，如细胞间钙信号传导和大脑内的代谢运输。
