Repeated use of betamethasone in rabbits: Effects of treatment variation on adrenal suppression, pulmonary maturation, and pregnancy outcome

Citation
L. Pratt et al., Repeated use of betamethasone in rabbits: Effects of treatment variation on adrenal suppression, pulmonary maturation, and pregnancy outcome, AM J OBST G, 180(4), 1999, pp. 995-1005
Citations number
29
Categorie Soggetti
Reproductive Medicine","da verificare
Journal title
AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
ISSN journal
00029378 → ACNP
Volume
180
Issue
4
Year of publication
1999
Pages
995 - 1005
Database
ISI
SICI code
0002-9378(199904)180:4<995:RUOBIR>2.0.ZU;2-S
Abstract
OBJECTIVE: The aim of the study was to determine whether reduced birth weig ht, adrenal suppression, and lung maturation occur in parallel and are cumu lative with increasing courses of betamethasone. STUDY DESIGN: Time-bred rabbits were assigned to a control group or to rece ive saline solution or 1, 2, or 3 courses of betamethasone (early treatment , beginning day 19). Two additional groups (n = 5 per group) were given 1 o r 2 late courses (late treatment). Birth weight, serum cortisol, adrenal 17 alpha-hydroxylase (P450c17) messenger ribonucleic acid and fetal lung surf actant proteins A and B were quantified on day 27. RESULTS: Fetal weight was inversely proportional to the number of courses, with late treatment having a greater effect. Maternal cortisol and P450c17 levels were progressively suppressed with each early course, but fetal cort isol and P450c17 levels were only suppressed after 3 courses. A single late treatment profoundly suppressed both maternal and fetal cortisol and P450c 17 messenger ribonucleic acid levels. In contrast, fetal lung surfactant pr oteins A and B increased progressively with betamethasone courses, regardle ss of timing. CONCLUSIONS: Time from last injection to delivery determined adrenal suppre ssion, whereas total betamethasone courses determined surfactant protein pr oduction. Lower birth weight was dependent on the number of courses and was greater with late treatment.