Neonatal dexamethasone induces premature microvascular maturation of the alveolar capillary network.

Détails

ID Serval
serval:BIB_1B562A8B24F2
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Neonatal dexamethasone induces premature microvascular maturation of the alveolar capillary network.
Périodique
Developmental Dynamics
Auteur(s)
Roth-Kleiner M., Berger T.M., Tarek M.R., Burri P.H., Schittny J.C.
ISSN
1058-8388 (Print)
ISSN-L
1058-8388
Statut éditorial
Publié
Date de publication
2005
Peer-reviewed
Oui
Volume
233
Numéro
4
Pages
1261-1271
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Résumé
Postnatal glucocorticoid treatment of preterm infants was mimicked by treating newborn rats with dexamethasone (0.1-0.01 microg/g, days 1-4). This regimen has been shown to cause delayed alveolarization. Knowing that microvascular maturation (transformation of double- to single-layered capillary networks in alveolar septa) and septal thinning prevent further alveolarization, we measured septal maturation on electron photomicrographs in treated and control animals. In treated rats and before day 10, we observed a premature nonreversing microvascular maturation and a transient septal thinning, which both appeared focally. In vascular casts of both groups, we observed contacts between the two capillary layers of immature alveolar septa, which were predictive for capillary fusions. Studying serial electron microscopic sections of human lungs, we were able to confirm the postulated fusion process for the first time. We conclude that alveolar microvascular maturation indeed occurs by capillary fusion and that the dexamethasone-induced impairment of alveolarization is associated with focal premature capillary fusion.
Mots-clé
Animals, Animals, Newborn/growth & development, Animals, Newborn/physiology, Capillaries/drug effects, Capillaries/growth & development, Dexamethasone/pharmacology, Female, Humans, Infant, Male, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Neovascularization, Physiologic/drug effects, Pulmonary Alveoli/blood supply, Pulmonary Alveoli/drug effects, Rats, Rats, Sprague-Dawley
Pubmed
Web of science
Open Access
Oui
Création de la notice
24/01/2008 21:41
Dernière modification de la notice
08/05/2019 15:16
Données d'usage