Understanding the Blood-Brain Barrier

The blood-brain barrier is not a solid barrier around the brain but rather a concept representing the properties of cells lining the brain's blood vessels, particularly the endothelial cells. These cells possess distinct receptors and tight junctions that regulate the entry and exit of various molecules, such as glucose, which is essential for brain function. Glucose enters the brain through a receptor-mediated process, allowing it to be delivered to neurons without the ability of the brain to store glucose. The variations in endothelial cell properties compared to peripheral cells illustrate the brain's specialized mechanisms designed to protect its neurons.