Modes of regulation of laminin-5 production by rat astrocytes

Astrocytes have a prominent role in central nervous system-specific microvascular growth and function. Extracellular matrix molecules (ECMs) bind to specific adhesion molecules - integrins. These adhesion complexes are responsible for tissue integrity and cellular sig nai ring. We have era mined astrocyte-endothelial cell interactions in relation to expression of the ECM laminin-5. Astrocytes produce laminin-5 in cell culture. The production is enhanced by endothelial cells. Direct cellular contact possibly involving a pi integrin or an insoluble matrix compound detected by the astrocytes is responsible for the induction of astrocytic laminin production by endothelial cells. Hypoxia also influences ECM production. The described regulation goes in concert with the known effects of astrocyte-endothelial cell interaction and stresses its importance for microvascular integrity. (C) 2000 Elsevier Science Ltd. All rights reserved.