Antioxidant enzyme responses to hyperoxia in preterm and term rats after prenatal dexamethasone administration

S. E. Keeney, M. J. Mathews, D. K. Rassin

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Although prenatal steroid therapy is known to enhance in utero maturation of the surfactant and antioxidant enzyme systems, little is known about the effects of steroids on the antioxidant system after birth. We measured activities of the antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase, in lung homogenates from both preterm and term rat pups after prenatal dexamethasone treatment. Enzyme activities were measured at birth and after exposure to >98% oxygen. Dexamethasone treatment resulted in significantly higher survival of the preterm pups at 24 h (91.3% for dexamethasone versus 57% for saline). In preterm pups, the activities of catalase and superoxide dismutase at birth were higher after dexamethasone treatment (p < 0.05). However, after 24 h of hyperoxic exposure, there were no differences in activities of any of the antioxidant enzymes between the dexamethasone and control groups of prematurely born pups. In term pups, antioxidant enzyme activities did not differ significantly at birth; nor did they differ after 24 to 72 h of hyperoxic exposure in the dexamethasone and control treatment groups. Our results indicate that although prenatal dexamethasone treatment augments survival and catalase and superoxide dismutase activities at birth in preterm rat pups, dexamethasone does not result in altered early postnatal antioxidant enzyme activities after exposure to hyperoxia.

Original languageEnglish (US)
Pages (from-to)177-180
Number of pages4
JournalPediatric Research
Volume33
Issue number2
StatePublished - 1993

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Hyperoxia
Dexamethasone
Antioxidants
Enzymes
Parturition
Catalase
Superoxide Dismutase
Steroids
Control Groups
Premature Birth
Glutathione Peroxidase
Surface-Active Agents
Oxygen
Lung

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health

Cite this

Antioxidant enzyme responses to hyperoxia in preterm and term rats after prenatal dexamethasone administration. / Keeney, S. E.; Mathews, M. J.; Rassin, D. K.

In: Pediatric Research, Vol. 33, No. 2, 1993, p. 177-180.

Research output: Contribution to journalArticle

Keeney, S. E. ; Mathews, M. J. ; Rassin, D. K. / Antioxidant enzyme responses to hyperoxia in preterm and term rats after prenatal dexamethasone administration. In: Pediatric Research. 1993 ; Vol. 33, No. 2. pp. 177-180.
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