title: Hemolysis-associated pulmonary hypertension in thalassemia.
abstract: Accumulating evidence supports the existence of a condition involving hemolysis-associated pulmonary hypertension (PHT). Hemolysis-induced release of cell-free hemoglobin and red blood cell arginase, resulting in impaired nitric oxide bioavailability, endothelial dysfunction, and PHT, has been reported in sickle cell disease. Since thalassemia is also a condition of chronic hemolysis, these patients are at risk. The data demonstrate that hemolysis-induced dysregulation of arginine metabolism and PHT also occurs in thalassemia. Erythrocyte release of arginase during hemolysis contributes to the development of PHT. Therapies that maximize arginine and nitric oxide bioavailability may benefit patients with thalassemia.
authors.affiliation: Department of Emergency Medicine, Children's Hospital & Research Center at Oakland, 747 52nd Street, Oakland, California 94609, USA. claudiamorris@comcast.net
authors.forename: Claudia R
authors.initials: CR
authors.lastname: Morris
authors.forename: Frans A
authors.initials: FA
authors.lastname: Kuypers
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Kato
authors.forename: Lisa
authors.initials: L
authors.lastname: Lavrisha
authors.forename: Sandra
authors.initials: S
authors.lastname: Larkin
authors.forename: Titi
authors.initials: T
authors.lastname: Singer
authors.forename: Elliott P
authors.initials: EP
authors.lastname: Vichinsky
mesh_terms: D001119:Arginase / Q000097:blood*; D001120:Arginine / Q000097:blood; D004730:Endothelium, Vascular / Q000503:physiopathology; D004912:Erythrocytes / Q000201:enzymology; D006446:Hemoglobin E; D006461:Hemolysis; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D009569:Nitric Oxide / Q000097:blood; D009952:Ornithine / Q000097:blood; D013789:Thalassemia / Q000097:blood / Q000150:complications*; D014261:Tricuspid Valve / Q000503:physiopathology; D017085:alpha-Thalassemia / Q000097:blood / Q000150:complications / Q000235:genetics
chemical_list: D009569:Nitric Oxide; D006446:Hemoglobin E; D001120:Arginine; D009952:Ornithine; D001119:Arginase