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Differential effects of placental restriction on IGF-II, ACTH receptor and steroidogenic enzyme mRNA levels in the foetal sheep adrenal

Version 2 2024-06-05, 02:06
Version 1 2019-01-16, 15:06
journal contribution
posted on 2024-06-05, 02:06 authored by JT Ross, ID Phillips, G Simonetta, Julie OwensJulie Owens, JS Robinson, IC McMillen
We have investigated the effects of restriction of placental growth on foetal adrenal growth and adrenal expression of mRNAs for Insulin-like Growth Factor II (IGF-II), the IGF binding protein IGFBP-2, Steroidogenic Factor 1 (SF-1) and adrenocorticotrophic hormone (ACTH) receptor (ACTH-R) and the steroidogenic cytochrome P-450 enzymes: cholesterol side chain cleavage (CYP11A1), 17alpha-hydroxylase (CYP17) and 21-hydroxylase (CYP21A1); and 3beta-hydroxysteroid dehydrogenase/Delta5Delta4 isomerase (3betaHSD). Endometrial caruncles were removed from non-pregnant ewes before mating (placental restriction group; PR). The total adrenal: foetal weight ratio was higher in PR (n=6 foetuses) than in control foetuses (n=6 foetuses). There was no difference in plasma ACTH concentrations between the PR and control foetuses between 130 and 140 days gestation. Adrenal IGF-II mRNA levels were lower (P<0.05) in the PR group, however, adrenal IGFBP-2 mRNA levels were not different between the PR and control groups. Adrenal ACTH-R mRNA levels were also lower whilst CYP11A1 mRNA levels were increased (P<0.005) in the PR group. We conclude that foetal adrenal growth and steroidogenesis are stimulated as a consequence of foetal growth restriction and that factors other than ACTH are important in foetal adrenal activation during chronic, sustained hypoxaemia.

History

Journal

Journal of neuroendocrinology

Volume

12

Pagination

79-85

Location

Chichester, Eng.

ISSN

0953-8194

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2000, Blackwell Science Ltd

Issue

1

Publisher

Wiley