title: Effect of retinoic acid on oxygen-induced lung injury in the newborn rat.
abstract: Oxygen-induced lung injury is believed to lead to the development of bronchopulmonary dysplasia (BPD). To determine whether retinoic acid (RA) treatment prevents the development of BPD by minimizing lung injury, we investigated the effect of RA on the histopathologic characteristics of oxygen-induced lung injury in a newborn rat model. Eighteen rat pups were divided into three groups: room air-exposed control group (n=5), oxygen-exposed placebo group (n=7), and RA-treated oxygen-exposed group (n=6). Measurement of alveolar area, quantitation of secondary crest formation, microvessel count, evaluation of alveolar septal fibrosis, and smooth muscle actin (SMA) immunostaining were performed to assess oxygen-induced changes in lung morphology. Treatment of oxygen-exposed animals with RA resulted in a significant increase in mean alveolar area; however, it had no effect on the number of secondary crests and microvessel count. The degree of fibrosis and SMA expression showed a significant decrease in RA-treated animals. We conclude that RA treatment improves alveolar structure and decreases fibrosis in the newborn rat with oxygen-induced lung injury. Extrapolating these findings to humans, we speculate that similar treatment with RA may reduce lung injury in preterm infants at risk for BPD.
authors.affiliation: Department of Pediatrics, School of Medicine, Dokuz Eylul University, Izmir, Turkey.
authors.forename: Esra Arun
authors.initials: EA
authors.lastname: Ozer
authors.forename: Abdullah
authors.initials: A
authors.lastname: Kumral
authors.forename: Erdener
authors.initials: E
authors.lastname: Ozer
authors.forename: Nuray
authors.initials: N
authors.lastname: Duman
authors.forename: Osman
authors.initials: O
authors.lastname: Yilmaz
authors.forename: Sermin
authors.initials: S
authors.lastname: Ozkal
authors.forename: Hasan
authors.initials: H
authors.lastname: Ozkan
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000975:Antioxidants / Q000494:pharmacology*; D001997:Bronchopulmonary Dysplasia / Q000188:drug therapy* / Q000209:etiology* / Q000662:veterinary; D004195:Disease Models, Animal; D006801:Humans; D007231:Infant, Newborn; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects*; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012307:Risk Factors; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D014212:Tretinoin