Na+/H+ Exchanger (NHE)

Na⁺/H⁺ exchanger (sodium/hydrogen exchanger, NHE) family exchanges Na⁺ for H⁺ according to their concentration gradients, thus promotes the regulation of the stability of cytoplasmic pH and cell volume.

There are nine isoforms of NHE in humans, some NHEs function primarily on the plasma membrane, and others are present on intracellular organelles. NHE1 is expressed in the plasma membrane of virtually all tissues and plays an important role in cardiac health. NHE2 is expressed in the gastrointestinal (GI) tract and contributes to the maintenance of stomach pH and homeostasis, whereas NHE3 predominates in the GI tract and kidneys. NHE4 and NHE5 are abundant in the stomach and brain, respectively. NHE6-9 are expressed in the intracellular compartments of many organ system membranes, but of these NHE8 is the exception and expressed apically.