Yael Kenig-Kozlovsky, Rizaldy P Scott, Tuncer Onay, Isabel Anna Carota, Benjamin R Thomson, Hyea Jin Gil, Veronica Ramirez, Shinji Yamaguchi, Christine E Tanna, Stefan Heinen, Christine Wu, Radu V Stan, Janet D Klein, Jeff M Sands, Guillermo Oliver, Susan E Quaggin
Urinary concentrating ability is central to mammalian water balance and depends on a medullary osmotic gradient generated by a countercurrent multiplication mechanism. Medullary hyperosmolarity is protected from washout by countercurrent exchange and efficient removal of interstitial fluid resorbed from the loop of Henle and collecting ducts. In most tissues, lymphatic vessels drain excess interstitial fluid back to the venous circulation. However, the renal medulla is devoid of classic lymphatics. Studies have suggested that the fenestrated ascending vasa recta (AVRs) drain the interstitial fluid in this location, but this function has not been conclusively shown...
April 2018: Journal of the American Society of Nephrology: JASN