INSIGHT INTO THE REGULATION BY 2ND MESSENGER MOLECULES OF THE PERMEABILITY OF THE BLOOD-BRAIN-BARRIER

Recent advances in our knowledge of the blood-brain barrier have in pa rt been made by studying the properties and function of cerebral endot helial cells in vitro. After an era of working with a fraction, enrich ed in cerebral microvessels by centrifugation, the next generation of in vitro blood-brain barrier model systems was introduced, when the co nditions for routinely culturing the endothelial cells were establishe d. This review summarizes the results obtained mainly from this in vit ro approach. Different elements of the intracellular signaling messeng er systems have been detected in the course of our studies in the cere bral endothelial cells. It has been shown that the synthesizing enzyme s of and substrate proteins for the second messenger molecules are pre sent in the cerebral endothelial cells, and their activity and/or amou nt can change in pathological circumstances, i.e., during the formatio n of brain oedema. Pharmacological treatments interfering with the sec ond messenger systems proved to be effective in the prevention of brai n oedema formation. (C) 1994 Wiley-Liss, Inc.