Endothelium 532570 222179942 2008-06-27T23:16:07Z WadeSimMiser 170099 Reverted edits by [[Special:Contributions/66.161.125.41|66.161.125.41]] to last version by 192.35.79.70 (using [[WP:HG|Huggle]]) [[Image:Anatomy_artery.png|thumb|350px||right|Diagram showing the location of endothelial cells]] {{dablink|This article is about the lining of [[blood vessel]]s. For the endothelium of the [[cornea]], see [[corneal endothelium]]}} The '''endothelium''' is the thin layer of [[cell (biology)|cells]] that line the interior surface of [[blood vessel]]s, forming an interface between circulating [[blood]] in the [[lumen (anatomy)|lumen]] and the rest of the vessel wall. Endothelial cells line the entire [[circulatory system]], from the [[heart]] to the smallest [[capillary]]. These cells reduce [[turbulence]] of the flow of blood allowing the fluid to be pumped farther. Endothelial tissue is a specialized type of [[epithelium]] tissue (one of the four types of [[biological tissue]] in animals). More specifically, it is [[Squamous epithelium|simple squamous epithelium]]. Endothelium of the interior surfaces of the heart chambers are called [[endocardium]]. Both blood and lymphatic capillaries are composed of a single layer of endothelial cells. ==Function== Endothelial cells are involved in many aspects of vascular biology, including: * [[vasoconstriction]] and [[vasodilation]], and hence the control of [[blood pressure]] * [[coagulation|blood clotting]] ([[thrombosis]] & [[fibrinolysis]]) * [[atherosclerosis]] * formation of new blood vessels ([[angiogenesis]]) * [[inflammation]] and swelling ([[oedema]]) Endothelial cells also control the passage of materials — and the transit of [[white blood cell]]s — into and out of the bloodstream. In some organs, there are highly differentiated endothelial cells to perform specialized 'filtering' functions. Examples of such unique endothelial structures include the [[glomerulus (kidney)|renal glomerulus]] and the [[blood-brain barrier]]. ==Pathology== ''[[Endothelial dysfunction]]'', or the loss of proper endothelial function, is a hallmark for vascular diseases, and often leads to [[atherosclerosis]]. This is very common in patients with [[diabetes mellitus]], [[hypertension]] or other chronic pathophysiological conditions. One of the main mechanisms of endothelial dysfunction is the diminishing of [[nitric oxide]], often due to high levels of [[asymmetric dimethylarginine]], which interfere with the normal [[Arginine|L-arginine]]-stimulated [[Nitric oxide synthase|nitric oxide synthesis]]. ==See also== *[[Endothelium-derived relaxing factor]] ([[EDRF]]) *[[Robert F. Furchgott]] (1998 Nobel prize for discovery of EDRF) *[[Caveolae]] *[[Weibel-Palade body|Weibel-Palade bodies]] *[[Endothelial microparticle]]s *[[Endothelial progenitor cell|Endothelial progenitor cells]] *[[Endocardium]] *[[Tunica intima]] *[[Apelin]] *[[Susac's syndrome]] ==External links== * {{eMedicineDictionary|endothelium}} * {{UCDavisOrganology|Circulatory/vessels/capillaries1/capillaries3}} - "Capillaries, non-fenestrated (EM, Low)" * {{BUHistology|21402ooa}} * ''Endothelium: Journal of Endothelial Research'' [http://www.informaworld.com/smpp/title~content=t713617829] ==References== * Molecular Biology of the CELL, 4th edition, Alberts et al., 2002 [[Category:Cardiovascular system]] [[Category:Tissues]] [[bg:Ендотел]] [[ca:Endoteli]] [[de:Endothel]] [[es:Endotelio]] [[eo:Endotelio]] [[fr:Endothélium]] [[it:Tessuto endoteliale]] [[la:Endothelium]] [[nl:Endotheel]] [[ja:血管内皮]] [[nds:Endothel]] [[pl:Śródbłonek]] [[pt:Endotélio]] [[sr:Ендотел]] [[sv:Endotel]] [[vi:Tế bào nội mô]] [[zh:內皮細胞]]