Assessment of Blood–Brain Barrier Breakdown

The blood–brain barrier (BBB) is a structural and functional barrier which limits the free passage of ions and large molecules between the blood and brain. BBB functions are often impaired in neurological disorders, more often in vascular-related injuries, stroke, intracerebral, and subarachnoid hemorrhage. Recently, it has been demonstrated that injury to the BBB and the diffusion of serum proteins into the brain’s extravascular space are directly related to immediate astrocytic transformation followed by neuronal dysfunction and delayed structural damage. Despite the increasing awareness to the potential importance of the BBB as a diagnostic and therapeutic target, there is still clear lack of quantitative and sensitive methods to measure BBB permeability. Here, we present a novel dynamic approach to detect and quantify BBB breakdown in the rat cerebral cortex using in vivo imaging. We further present alternative common methodologies.