What is the blood-brain barrier, and why is it important?
The blood-brain barrier (BBB) is a highly selective permeability barrier that protects the central nervous system (CNS) from toxins and pathogens. It is formed by endothelial cells with tight junctions, astrocytes, and pericytes. The BBB allows the passage of essential nutrients while restricting harmful substances. However, it can be a double-edged sword in toxicology as it also limits the entry of therapeutic drugs designed to treat CNS disorders. Certain toxins, such as heavy metals and pathogens, can disrupt the BBB, leading to neurological damage.
