Vasa recta 4031111 211515743 2008-05-10T19:34:59Z Anticipation of a New Lover's Arrival, The 6510232 usage {{Infobox Artery | Name = {{PAGENAME}} | Latin = arteriolae rectae renis | GraySubject = 253 | GrayPage = 1224 | Image = Kidney nephron.png | Caption = A nephron, the vasa recta is labelled ''arteria recta'' | Image2 = | Caption2 = | BranchFrom = [[Arcuate arteries of the kidney]], [[efferent arteriole]] | BranchTo = [[Straight venules of kidney]], [[arcuate vein]] | Vein = | Supplies = | MeshName = | MeshNumber = | DorlandsPre = a_62 | DorlandsSuf = 12156708 | }} :''For the intestinal structure, see [[Vasa recta (intestines)]]'' In the [[renal circulation|blood supply of the kidney]], the '''vasa recta renis''' (or '''straight arteries of kidney''', or '''straight arterioles of kidney''') form a series of straight capillaries (''recta'' is from the [[Latin language|Latin]] for "straight") that descend from the [[renal cortex|cortex]] into the [[renal medulla|medulla]]. These vessels branch off the [[efferent arteriole]]s of [[juxtamedullary nephron]]s (those [[nephron]]s closest to the medulla), enter the medulla, and surround the [[loop of Henle]]. ==Histology== On a slide, vasa recta can be distinguished from the tubules of the [[loop of Henle]] by the presence of blood.<ref>{{BUHistology|15802loa}}</ref> ==Function== Each of the vasa recta has a hairpin turn in the medulla and carries blood at a very slow rate, two factors crucial in the maintenance of [[countercurrent exchange]] that prevent washout of the concentration gradients established in the renal medulla.<ref>{{GeorgiaPhysiology|7/7ch08/7ch08p07}}</ref> The maintenance of this concentration gradient is one of the components responsible for the kidney's ability to produce concentrated [[urine]]. On the descending portion of the vasa recta, NaCl and urea are reabsorbed into the blood, while water is secreted. On the ascending portion of the vasa recta, NaCl and urea are secreted into the interstitium, while water is reabsorbed. ==Nomenclature== According to [[Terminologia Anatomica]]<ref>{{Dorlands|a_62|12156708}}</ref>, the term "vasa recta renis" is an alternate name for "arteriolae rectae renis", and a separate term, [[Straight venules of kidney|venulae rectae renis]], is used to identify the venous portion. However, other sources consider "vasa recta renis" to refer to both the arterial and venous portions.<ref>{{BUHistology|15804loa}}</ref> The "renis" is often omitted, but there do exist two other structures with the same name: * [[vasa recta (intestines)]] (in the [[ileum]] and [[jejunum]])<ref>{{NormanAnatomy|jejunumileum}}</ref> * the straight portion of the [[seminiferous tubule]]<ref>{{eMedicineDictionary|vasa+recta}}</ref> ==Pathology== The slow blood flow in vasa recta makes them a likely place of [[thrombosis]] in hypercoagulable states, or erythrocyte sickling in [[sickle cell disease]]. [[Ischemia]] that results may lead to [[renal papillary necrosis]]. ==References== <references/> ==External links== * {{UIUCHistologySubject|937}} * [http://gena.ontology.ims.u-tokyo.ac.jp:8081/mov/cgi-bin/movOntologyView.php?type=UMLS&target=C1183211&mode=search UMLS] {{kidney}} {{circulatory-stub}} [[Category:Kidney]] [[ja:直細動脈]]