Blood-brain barrier (BBB)

Definition

The blood-brain barrier is a selective permeability barrier that separates the circulating blood from the brain and extracellular fluid in the central nervous system (CNS). It protects the brain from foreign substances in the blood that may injure the brain, regulates transport of nutrients and waste, and maintains a stable environment for the brain.

Related terms

Neuroglia: Supportive cells in the nervous system that provide physical support, nutrient transport, and waste removal for neurons.

Cerebrospinal Fluid (CSF): A clear fluid found in the brain and spinal cord that acts as a cushion for the brain's cortex, providing basic mechanical and immunological protection to the CNS.

Endothelial Cells: Cells that line the interior surface of blood vessels and form an integral component of the BBB by restricting passage of substances between the bloodstream and neural tissue