The in vitro blood-brain barrier: the assessment of drug transport to the brain

To provide an in vitro system for studying brain capillary functions, we have developed a coculture procedure that closely mimics the in vivo situation, by culturing brain capillary endothelial cells on one side of a filter and astrocytes on the other. The strong correlation between the in vivo (Oldendorf method) and in vitro (coculture) drug transport, the relative ease with which such cocultures can be produced in large quantities, and the reproducibility of the system, provide evidence for an efficient system for the screening of drugs that are active in the central nervous system.