Gefäßdurchlässigkeitsstörungen

Gefäßdurchlässigkeit, also known as vascular permeability, refers to the ability of blood vessels to allow substances and cells to pass through their walls. This process is crucial for various physiological functions, including nutrient and oxygen delivery to tissues, and the removal of waste products. It also plays a significant role in the immune response, enabling immune cells to migrate from the bloodstream to sites of infection or inflammation.

The structure of blood vessel walls, particularly the endothelium, a single layer of cells lining the interior of blood vessels, dictates their permeability. The junctions between endothelial cells can either be tight, restricting passage, or somewhat loose, allowing for controlled transport. This permeability can be influenced by several factors, including chemical mediators like histamine and bradykinin, mechanical stress, and inflammatory signals.

When vascular permeability increases abnormally, it can lead to pathological conditions. For instance, in inflammation, increased permeability allows plasma proteins and immune cells to accumulate in the affected tissue, contributing to swelling and redness. In certain diseases, such as sepsis or severe allergic reactions, a widespread and uncontrolled increase in vascular permeability can result in a dangerous drop in blood pressure and organ damage. Conversely, decreased vascular permeability is also important for maintaining tissue homeostasis and preventing unwanted leakage. Understanding and modulating vascular permeability is a key area of research in medicine, with implications for treating inflammatory diseases, cancer, and other conditions.