Department of Medicine, Nephrology Research Group, Laval University, Quebec City, Québec, Canada.
Cardiometabolic Axis, School of Kinesiology and Physical Activity Sciences, University of Montréal, Montréal, Quebec, Canada.
J Cell Physiol. 2021 Mar;236(3):1712-1729. doi: 10.1002/jcp.29997. Epub 2020 Aug 10.
Na -K -Cl cotransporter 2 (NKCC2; SLC12A1) is an integral membrane protein that comes as three splice variants and mediates the cotranslocation of Na , K , and Cl ions through the apical membrane of the thick ascending loop of Henle (TALH). In doing so, and through the involvement of other ion transport systems, it allows this nephron segment to reclaim a large fraction of the ultrafiltered Na , Cl , Ca , Mg , and HCO loads. The functional relevance of NKCC2 in human is illustrated by the many abnormalities that result from the inactivation of this transport system through the use of loop diuretics or in the setting of inherited disorders. The following presentation aims at discussing the physiological roles and molecular characteristics of Na -K -Cl cotransport in the TALH and those of the individual NKCC2 splice variants more specifically. Many of the historical and recent data that have emerged from the experiments conducted will be outlined and their larger meaning will also be placed into perspective with the aid of various hypotheses.
钠-钾-氯共转运蛋白 2（NKCC2；SLC12A1）是一种整合膜蛋白，有三种剪接变体，通过亨利氏袢升支粗段（TALH）的顶膜介导 Na+、K+和 Cl-的共转运。通过这种方式，并通过其他离子转运系统的参与，它允许这个肾单位段回收超滤的 Na+、Cl-、Ca2+、Mg2+和 HCO3-负荷的很大一部分。通过使用袢利尿剂或遗传性疾病使该转运系统失活，导致 NKCC2 在人类中的许多异常，说明了 NKCC2 的功能相关性。以下介绍旨在讨论 TALH 中 Na+-K+-Cl-共转运的生理作用和分子特征，以及各个 NKCC2 剪接变体的更具体特征。将概述从实验中得出的许多历史和最新数据，并借助各种假设，将其更大的意义与实际情况联系起来。
