Abstract |
To determine whether prenatal corticosteroid therapy had adverse effects on the tolerance of the newborn lung to prolonged high O2 exposure, pregnant rats were given injections of dexamethasone (0.2 mg/kg) at 48 and 24 hours prior to parturition, and the newborn pups were placed in 96% to 98% O2 for the first seven days of life. Dexamethasone treatment resulted in significant decreases in body weight (-17%), lung weight (-30%), lung weight/body weight (-22%), and lung DNA (-18%) compared to untreated rat pups. Despite this growth inhibition, the dexamethasone-treated pups had improved survival in hyperoxia (36/48 = 75% vs 29/48 = 60% for untreated rats, P = .055). In addition, substantial "catch-up" lung growth had occurred by seven days and was complete in 28-day-old rats. Dexamethasone did not interfere with normal pulmonary antioxidant enzyme responses to hyperoxia. Thus, prenatal dexamethasone did not compromise the relative tolerance of the newborn to pulmonary O2 toxicity.
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Authors | L Frank, J Summerville, D Massaro |
Journal | Pediatrics
(Pediatrics)
Vol. 65
Issue 2
Pg. 287-93
(Feb 1980)
ISSN: 0031-4005 [Print] United States |
PMID | 7188811
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
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Topics |
- Animals
- Animals, Newborn
- Dexamethasone
(pharmacology)
- Female
- Lung
(drug effects, embryology, physiology)
- Maternal-Fetal Exchange
- Organ Size
(drug effects)
- Oxygen
(toxicity)
- Pregnancy
- Rats
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