title: Effect of temporary tracheal occlusion on the endothelin system in experimental cases of diaphragmatic hernia.
abstract: Previously, the authors have shown that tracheal occlusion (TO) partially reverses the onset of congenital diaphragmatic hernia (CDH)-induced pulmonary hypertension (PH) and abnormal pulmonary vascular development whereas release of the occlusion (TR) abolishes these clinical benefits. As a consequence of their mitogenic and vasoactive properties, the authors hypothesize that the expression of endothelin (ET)-1 and ET receptor (ETA) genes is increased in lungs of CDH lambs, and that this increase is abolished partially in CDH + TO but not in CDH + TO + TR. A surgical left-sided CDH was created in fetal lambs at 80 days of gestation (gd), followed by TO at 108 gd, and by TR at 129 gd. Four groups were compared: CDH, CDH + TO, CDH + TO + TR, and nonoperated controls (C). Assessment of mRNA expression by Northern blot showed significantly lower ET-1 and ETA levels in the CDH group than in the CDH + TO +/- TR groups (P < .05). Endothelin protein expression levels were lower in CDH +/- TO +/- TR groups when compared with controls for airways and vessels (P < .05) with the exception of endothelial cells. In contrast, ETA protein expression levels were higher in CDH +/- TO +/- TR groups compared with controls for airways and blood vessels smooth muscles (P < .05). These results suggest that involvement of the endothelin system in the pulmonary hypertension associated with CDH is limited. However, the endothelin system appears to be modulated during development.
authors: Pediatrics, Centre Hospitalier Universitaire de Québec, Laval University, Sainte-Foy, Québec, Canada.
authors: Marc
authors: M
authors: Cloutier
authors: Tommy
authors: T
authors: Seaborn
authors: Bruno
authors: B
authors: Piedboeuf
authors: Ioana
authors: I
authors: Bratu
authors: Hélène
authors: H
authors: Flageole
authors: Jean-Martin
authors: JM
authors: Laberge
mesh_terms: D000818:Animals; D021721:Balloon Occlusion / Q000009:adverse effects* / Q000379:methods; D015152:Blotting, Northern; D004195:Disease Models, Animal; D019332:Endothelin-1 / Q000096:biosynthesis / Q000235:genetics; D005315:Fetal Diseases / Q000503:physiopathology / Q000628:therapy*; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D006548:Hernia, Diaphragmatic / Q000150:complications / Q000378:metabolism; D065630:Hernias, Diaphragmatic, Congenital; D007124:Immunoenzyme Techniques; D008168:Lung / Q000002:abnormalities / Q000098:blood supply / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D044022:Receptor, Endothelin A / Q000096:biosynthesis / Q000235:genetics; D012756:Sheep; D014132:Trachea
chemical_list: D019332:Endothelin-1; D012333:RNA, Messenger; D044022:Receptor, Endothelin A