title: Mg2+ efflux is accomplished by an amiloride-sensitive Na+/Mg2+ antiport.
abstract: Mg2+ efflux from Mg2+-preloaded chicken erythrocytes is caused by an electroneutral Na+/Mg2+ antiport. It depends specifically on extracellular Na+, according to Michaelis-Menten kinetics (Km = 25 mM), and is reversibly noncompetitively inhibited by amiloride (Ki = 0.59 mM). In contrast to Na+/H+ antiport, Li+, Ca2+ and N-ethylmaleimide do not interfere with Na+/Mg2+ antiport. The Na+/Mg2+ antiport is driven by the intracellular/extracellular Mg2+ gradient.
authors.forename: T
authors.initials: T
authors.lastname: Günther
authors.forename: J
authors.initials: J
authors.lastname: Vormann
mesh_terms: D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D002731:4-Chloromercuribenzenesulfonate / Q000494:pharmacology; D000584:Amiloride / Q000494:pharmacology*; D000818:Animals; D017920:Antiporters; D002118:Calcium / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism*; D002645:Chickens; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D005033:Ethylmaleimide / Q000494:pharmacology; D007700:Kinetics; D008094:Lithium / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism*; D011719:Pyrazines / Q000494:pharmacology*; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers
chemical_list: D017920:Antiporters; D002352:Carrier Proteins; D011719:Pyrazines; D017923:Sodium-Hydrogen Exchangers; C046250:sodium-magnesium antiporter; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; D002731:4-Chloromercuribenzenesulfonate; D000584:Amiloride; D008094:Lithium; D012964:Sodium; D008274:Magnesium; D005033:Ethylmaleimide; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D002118:Calcium