Blood vessel endothelial cells, also known as vascular endothelial cells, form the delicate inner lining of the complex circulatory system, including arteries and veins. These cells form a single, continuous monolayer inside every blood vessel, acting as a crucial biomolecular barrier between the blood, and the rest of the body tissues. They perform various fundamental biological functions, ranging from maintenance of vessel integrity to blood clotting regulation. Additionally, they control the transportation of fluids, molecules, and blood particulate matter from and into the bloodstream.
One of the primary functions of blood vessel endothelial cells is to maintain vascular homeostasis - a stable environment within the blood vessels. They accomplish this through several methods: they control vasomotor tone, i.e. the degree of contraction and dilation of blood vessels, by secreting vasoactive substances such as nitric oxide and endothelin; mediate responses to inflammatory stimuli; and they also regulate angiogenesis, the process of new blood vessel formations. Blood vessel endothelial cells play a significant role in preventing blood clot formation by generating a slick, non-thrombogenic surface that disallows platelets or coagulant proteins from adhering to it.
Blood vessel endothelial cells are sensitive to various stimuli, including shear stress caused by blood flow, and they can respond by altering their morphology, function, and gene expression. This ability to adapt enables blood vessels to remodel and ensure the adequate delivery of nutrients and oxygen to all tissues, regardless of physiological demand variations. Conversely, endothelial dysfunction, often associated with a reduction in the bioavailability of endothelium-derived nitric oxide, can lead to the development of pathological conditions such as atherosclerosis, hypertension, diabetes mellitus, and even aging-related diseases.
(This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.)
