The BBB is a highly specialized structure in the Central nervous system (CNS) between the blood circulation and the brain parenchyma. It is composed of highly specialized blood vessel endothelial cells which together with pericytes, and astrocyte endfeet allows very selective transport from the blood to the brain and vice versa. The whole structure, endothelial cells, pericytes and astrocytes, is called neurovascular unit.
Functions of BBB:
- Allow selective passage of molecules to brain
- Prevents unwanted macromolecules and cells to enter brain parenchyma
- Control ionic composition interstitial fluid that is important for proper synaptic signaling function
Please read the following peer-reviewed article to know about blood-brain barrier