Endothelfunktionsverlust

Endothelial function refers to the physiological capabilities of the endothelium, the monolayer of endothelial cells lining the vasculature, to regulate vascular tone, hemostasis, and inflammatory responses. The endothelium modulates vessel dilation primarily through nitric oxide (NO) and also via prostacyclin and endothelin-1, balancing vasodilation and vasoconstriction. It provides anti-thrombotic and anti-atherogenic properties by limiting platelet aggregation and leukocyte adhesion and by maintaining a selective barrier that controls substance exchange between blood and tissues. The endothelium also participates in immune signaling, angiogenesis, and vascular remodeling in response to injury and metabolic cues.

Endothelial function can be assessed noninvasively by tests such as flow-mediated dilation (FMD) of the brachial artery, which measures NO-mediated vasodilation, or by peripheral arterial tonometry and certain biochemical markers like von Willebrand factor and soluble adhesion molecules. Dysfunction is commonly defined as impaired vasodilatory response and is an early indicator of cardiovascular risk.

Risk factors such as aging, smoking, diabetes, hypertension, dyslipidemia, obesity, and sedentary lifestyle impair endothelial function. It is observed in atherosclerosis and metabolic syndrome and often precedes overt cardiovascular disease.

Interventions to improve endothelial function include regular aerobic exercise, weight loss, smoking cessation, and a diet rich in fruits, vegetables, and omega-3 fatty acids. Pharmacologic strategies that favor NO bioavailability—statins, ACE inhibitors, ARBs, and certain antidiabetic agents—may also improve endothelial function. While useful as a biomarker, endothelial function testing is not routinely used for diagnosis in most clinical settings but can aid risk stratification in research and select patients.