REGULATION OF GAP JUNCTION COMMUNICATION BY GROWTH-FACTORS FROM NONNEURAL CELLS TO ASTROGLIA - A BRIEF REVIEW

Astrocytes are coupled by gap junctions, which are composed of connexi ns, channel-forming proteins. Connexin43 is the predominant connexin o f astrocytes. Gap junctions assemble astrocytes into functional syncyt ia permitting exchange of small molecules including metabolites, catab olites, and second messenger molecules. Thus, gap junctions of astrogl ial cells serve the maintenance of extra- and intra-cellular homeostas is in the brain and eventually ascertain neuronal functions. Alteratio ns in astroglial cell coupling can disturb this equilibrium resulting in neuronal dysfunction and death. Growth factors are an important cla ss of substances that can influence coupling in non-neural cells. Seve ral groups have recently carried the analyses of gap junction regulati on by cytokines to the level of neural cells. This review summarizes t he recent progress in this field and outlines directions of future res earch. GLIA 24:32-38, 1998. (C) 1998 Wiley-Liss, Inc.