title: Increased neutrophil mediator release in patients with pulmonary hypertension--suppression by inhaled iloprost.
abstract: Polymorphonuclear neutrophils (PMN) have been implicated in various vascular inflammatory processes. We isolated PMN from venous blood samples of 10 patients with severe primary pulmonary arterial hypertension (PPH), 7 patients with pulmonary hypertension secondary to chronic thromboembolism (CTEPH), and 12 healthy controls. When stimulated with the calcium-ionophore A23187, platelet activating factor (PAF) or the microbial agent n-formyl-Methionyl-Leucyl-Phenylalanine (fMLP), significantly increased release of elastase and superoxide anion was noted in both groups with pulmonary hypertension. Moreover, the neutrophils of CTEPH patients responded with an enhanced liberation of leukotriene (LT) B(4) and 5-hydroxyeicosatetraenoic acid (5-HETE). Inhalation of aerosolized iloprost (5 microg) caused a rapid decline in pulmonary vascular resistance, in both PPH and CTEPH. This hemodynamic response was paralleled by a significant suppression of ionophore- and ligand-induced elastase and superoxide release, as well as LTB(4) and 5-HETE formation. The neutrophil inhibitory effect of the inhalation maneuver was fully reproduced by in vitro incubation of neutrophils with 1-10 pg/ml iloprost for 2 hours. This is the first study to demonstrate that circulating neutrophils from patients with PPH and CTEPH possess an enhanced readiness to respond with inflammatory mediator generation to different stimulatory agents ex-vivo, and that PMN respiratory burst, elastase secretion and leukotriene generation are promptly reduced by an iloprost inhalation maneuver. Neutrophils might participate in the inflammatory processes in pulmonary arterial hypertension.
authors.affiliation: Department of Internal Medicine, Justus-Leipzig-University, Klinikstrasse 36, 35392 Giessen, Germany. Frank.Rose@innere.med.uni-giessen.de
authors.forename: Frank
authors.initials: F
authors.lastname: Rose
authors.forename: Katja
authors.initials: K
authors.lastname: Hattar
authors.forename: Sybille
authors.initials: S
authors.lastname: Gakisch
authors.forename: Friedrich
authors.initials: F
authors.lastname: Grimminger
authors.forename: Horst
authors.initials: H
authors.lastname: Olschewski
authors.forename: Werner
authors.initials: W
authors.lastname: Seeger
authors.forename: Annette
authors.initials: A
authors.lastname: Tschuschner
authors.forename: Ralph T
authors.initials: RT
authors.lastname: Schermuly
authors.forename: Norbert
authors.initials: N
authors.lastname: Weissmann
authors.forename: Jörg
authors.initials: J
authors.lastname: Hanze
authors.forename: Ulf
authors.initials: U
authors.lastname: Sibelius
authors.forename: Hossein A
authors.initials: HA
authors.lastname: Ghofrani
mesh_terms: D000280:Administration, Inhalation; D016022:Case-Control Studies; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000097:blood; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000209:etiology; D016285:Iloprost / Q000008:administration & dosage* / Q000494:pharmacology; D018836:Inflammation Mediators / Q000378:metabolism*; D019272:Leukocyte Elastase / Q000378:metabolism; D015289:Leukotrienes / Q000378:metabolism; D009504:Neutrophils; D011652:Pulmonary Circulation / Q000187:drug effects; D016897:Respiratory Burst; D013481:Superoxides / Q000378:metabolism; D013923:Thromboembolism / Q000150:complications; D014655:Vascular Resistance / Q000187:drug effects
chemical_list: D006893:Hydroxyeicosatetraenoic Acids; D018836:Inflammation Mediators; D015289:Leukotrienes; D013481:Superoxides; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D019272:Leukocyte Elastase; D016285:Iloprost