Pathways for Cerebral Blood Flow

This chapter describes cerebral blood vessel structure, function, and the exchange of gas and nutrients. Vessel anatomy and feeding territories in each of the brain lobes are described. Capillaries, pericytes, glial cells and neurons form an assembly called the neural vascular unit (NVU), which is an interface regulating vascular function. Cerebral blood vessels have a special barrier system, called the blood brain barrier (BBB), to prevent substances moving across the vascular wall. BBB disruption due to some defect may result in cerebral edema, which is excess accumulation of fluid in the intra- or extra-cellular spaces of the brain. O2/CO2 and nutrients/waste are supplied/excreted to/from brain tissue through the cerebrovascular network. Finally, the oxygen dissociation from hemoglobin, one of the most important functions of blood flow, is described in detail.