Brain recovery from injury secondary to stroke or trauma is a function of the cellular regeneration that follows injury and an important component of this regeneration involves the biology of the brain microvasculature which makes up the blood-brain barrier (BBB) in vivo. The Program Project will investigate four different cell biological or molecular biological aspects of the BBB. Project #1 involves molecular cloning of two model brain capillary-enriched protein (BEP) genes, i.e., the glucose transporter and gamma-glutamyltranspeptidase, and two model brain capillary-Specific protein (BSP) genes, i.e., the 45 KDa and 53 KDa brain capillary proteins. Project #2 will investigate the interactions of brain microvascular endothelial cells with astrocytic cells in tissue culture and putative astrocytic factors that are found to induce BBB-specific properties will be purified from astrocyte-conditioned medium. Project #3 will study modulation of the BBB glucose transporter at both paradigms: anoxia/hypoxia, experimental diabetes mellitus, developing effects of leukotrienes on the BBB as they relate to brain tumor biology; [14C]-AIB quantitative autoradiography techniques will be used to assess changes in BBB permeability and leukotriene receptor binding quantitatively. All four project will rely heavily on two central cores (a Biochemistry Core and a Morphology/Tissue Culture Core). Extensive utilization of the cores will provide a common vehicle for interaction amongst the five projects as well as four extension of blood-brain barrier research to the biochemical and molecular biological levels.