Department of Anatomy and the Water and Salt Research Center, Aarhus University, Aarhus, Denmark.
Compr Physiol. 2011 Apr;1(2):1031-56. doi: 10.1002/cphy.c100064.
The mammalian kidney is responsible for a multitude of homeostatic functions, which are mediated by both structural and functional diversity along the renal tubule. In this article, we focus on the major functions of the terminal portion of the renal tubule, the medullary collecting duct system. The role of the medullary collecting ducts in determining the composition of the final urine through controlled water, sodium, chloride, potassium and urea reabsorption, ammonia transport, and acid-base homeostasis is discussed. The molecular identity of the major channels and transporters that contribute to medullary collecting duct function are described in detail, including; aquaporins, urea transporters, the epithelial sodium channel (ENaC), the Na,K-ATPase, H-ATPase, Rh glycoproteins, and sodium bicarbonate transporters. Knowledge gained from studies in knockout mice is also discussed.
哺乳动物的肾脏负责多种体内平衡功能，这些功能是通过沿肾小管的结构和功能多样性来介导的。在本文中，我们专注于肾小管的末端部分，即髓袢收集管系统的主要功能。讨论了髓袢收集管在通过控制水、钠、氯、钾和尿素重吸收、氨转运以及酸碱平衡来确定终尿成分方面的作用。详细描述了有助于髓袢收集管功能的主要通道和转运体的分子特征，包括：水通道蛋白、尿素转运体、上皮钠通道（ENaC）、Na+，K+-ATP 酶、H+-ATP 酶、Rh 糖蛋白和碳酸氢盐转运体。还讨论了从敲除小鼠研究中获得的知识。
