The Na+/H+ exchanger isoform 1.
The Na+/H+ exchanger (NHE) isoform 1 is a ubiquitously expressed integral membrane protein which regulates intracellular pH in mammalian cells. Nine isoforms of the Na+/H+ exchanger have been identified. The isoform first discovered has two domains: an N-terminal membrane domain containing approximately 500 amino acids and a C-terminal regulatory domain containing approximately 315 amino acids. The exchanger, which resides in the plasma membrane, exchanges an intracellular proton for an extracellular sodium, thereby regulating intracellular pH. It is involved in cell growth and differentiation, cell migration, and regulation of sodium fluxes. The Na+/H+ exchanger plays an important role in myocardial damage during ischemia and reperfusion and has recently been implicated as a mediator of cardiac hypertrophy. Inhibitors of the Na+/H+ exchanger, which may prove useful in the clinical treatment of these conditions, are currently being developed and clinical trials are underway.
Fliegel
Larry
L
Canadian Institute of Health Research Membrane Protein Research Group and the Department of Biochemistry, University of Alberta, Edmonton, Alta, T6G 2H7, Canada. lfliegel@ualberta.ca
D000818:Animals; D006332:Cardiomegaly / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D002462:Cell Membrane / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009206:Myocardium / Q000201:enzymology* / Q000473:pathology; D017434:Protein Structure, Tertiary / Q000235:genetics; D011522:Protons; D015427:Reperfusion Injury / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D011522:Protons; D017923:Sodium-Hydrogen Exchangers; D012964:Sodium