Educational objective: The blood-brain barrier is formed by ti | Uworld | Step 1

Educational objective: The blood-brain barrier is formed by tight junctions between nonfenestrated capillary endothelial cells that prevent the paracellular passage of fluid and solutes. This barrier only permits the passage of substances from the blood to the brain via transcellular movement across the endothelial plasma membrane, which is limited by diffusion or carrier-mediated transport.