blodnäringsbarriären

The blood-brain barrier, known in Swedish as blod-hjärnbarriären or sometimes simply blodnäringsbarriären, is a highly selective semipermeable border that separates the circulating blood from the brain and extracellular fluid in the central nervous system. It is composed of endothelial cells, which are a type of cell that lines the interior surface of blood vessels. These endothelial cells are connected by tight junctions, which are structures that prevent the passage of most substances from the bloodstream into the brain.

The primary function of the blood-brain barrier is to protect the brain from harmful substances that may be present in the blood, such as toxins and pathogens. It also plays a crucial role in maintaining a stable environment for the brain, ensuring that the concentration of essential nutrients and ions remains within a narrow range. While the barrier effectively blocks many substances, it allows for the passage of essential molecules like oxygen, glucose, and certain amino acids.

The formation and maintenance of the blood-brain barrier are complex processes involving various cell types, including astrocytes and pericytes, in addition to the endothelial cells. Disruptions to the blood-brain barrier can occur due to various factors, including injury, inflammation, and certain diseases, leading to potential neurological problems. Research into the blood-brain barrier is ongoing, aiming to understand its mechanisms and develop strategies to manipulate its permeability for therapeutic purposes.