Blodretinabarriären

The Blood-Brain Barrier (BBB) is a highly selective semipermeable border of endothelial cells that prevents solutes in the circulating blood from non-selectively crossing into the brain tissue during exchanges. It is a crucial defense mechanism that protects the central nervous system from potential toxins, pathogens, and disruptions in homeostasis. The BBB is formed by specialized capillaries that are different from those found elsewhere in the body. These capillaries have tight junctions between their endothelial cells, significantly restricting the passage of substances. Additionally, astrocytes, a type of glial cell, play a vital role in maintaining the integrity and function of the BBB by enveloping the capillaries. This complex structure ensures that only essential molecules, such as glucose and oxygen, are able to cross into the brain, while many other substances are excluded. The BBB's protective nature also presents challenges for drug delivery to the brain, as many therapeutic agents are unable to penetrate this barrier effectively. Research into methods to overcome or temporarily open the BBB for targeted drug delivery is an active area of scientific investigation.