Loop of Henle

-Na+/Cl- -move out of the thick ascending limb and into the medulla -by active transport against the conc gradient (through carrier proteins which requires ATP) * The high conc of ions in the medulla reduces the water potential in the medulla. This causes water to move out of descending limb into the medulla . this causes high concentration of Na+/Cl- in bottom of the loop of Henle . Na+/Cl- -move out of the thin ascending limb and into the medulla. -by facilitated diffusion from a high to low concentration. * This movement causes there to be a lower concentration of ions in the thick ascending limb.