Fig. 1

Schematic of blood brain barrier (BBB) structure and the neurovascular unit (NVU). The brain vasculature is lined with a single layer of endothelial cells that is tightly sealed by tight and adherens junction molecules. It is further insulated by pericytes and astrocytic endfoot processes and in total are referred to as the NVU. Efflux and influx transporters expressed on BBB endothelial cells selectively allow the entry or exit of molecules into or out of the brain