title: Membrane ion transport in Bartter's syndrome: evidence for a new syndrome subtype.
abstract: Fifteen patients with Bartter's syndrome (hyponatremic hypochloremic hypokalemic metabolic alkalosis) were compared with 15 healthy volunteers. Red blood cell Na+/H+ and Cl-/HCO3- exchanges were enhanced in all patients with Bartter's syndrome. In calciuric normomagnesemic patients, sensitive to nonsteroidal anti-inflammatory drugs (classic Bartter's syndrome), red blood cell Na+,K+,2Cl- cotransport was markedly reduced, calcium-dependent K+ permeability was moderately increased, and up to 60% of sodium permeability was represented by cAMP-activated fraction (presumably human analog of beta-isoform of Na+/H+ exchange). In noncalciuric hypomagnesemic patients insensitive to indomethacin (Gitelman's syndrome), Na+,K+,2Cl- cotransport was enhanced, Na+ permeability was increased due to calmodulin-dependent fraction, and calcium-dependent K+ permeability was markedly enhanced. A new subtype of Bartter-like syndrome ("variant Bartter's syndrome") has been described in which calciuria, hypomagnesemia, and insensitivity to nonsteroidal anti-inflammatory drugs were associated with decreased Na+,K+,2Cl- cotransport, enhanced calmodulin-activated fraction of Na+ influx, and reduced calcium-dependent K+ permeability.
authors.affiliation: Chorley Institute for Hypertension, Sheba Medical Center Tel Hashomer and Sackler Faculty of Medicine, Tel Aviv University, Israel.
authors.forename: W
authors.initials: W
authors.lastname: Koren
authors.forename: E
authors.initials: E
authors.lastname: Peleg
authors.forename: T
authors.initials: T
authors.lastname: Rosenthal
authors.forename: Y V
authors.initials: YV
authors.lastname: Postnov
mesh_terms: D000293:Adolescent; D000328:Adult; D001477:Bartter Syndrome / Q000097:blood*; D001692:Biological Transport; D002118:Calcium / Q000097:blood; D002147:Calmodulin / Q000494:pharmacology; D002352:Carrier Proteins / Q000097:blood; D002712:Chlorides / Q000097:blood; D004573:Electrolytes / Q000097:blood*; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D011188:Potassium / Q000097:blood; D015221:Potassium Channels / Q000378:metabolism; D012016:Reference Values; D012964:Sodium / Q000097:blood; D017923:Sodium-Hydrogen Exchangers / Q000097:blood; D028021:Sodium-Potassium-Chloride Symporters; D013148:Spironolactone / Q000494:pharmacology
chemical_list: D002147:Calmodulin; D002352:Carrier Proteins; D002712:Chlorides; D004573:Electrolytes; D015221:Potassium Channels; D017923:Sodium-Hydrogen Exchangers; D028021:Sodium-Potassium-Chloride Symporters; D013148:Spironolactone; D012964:Sodium; D011188:Potassium; D002118:Calcium