Research article - Peer-reviewed, 2003
Sex differences in oestrogen receptor levels in adrenal glands of sheep during the breeding season
van Lier E, Meikle A, Bielli A, Akerberg S, Forsberg M, Sahlin LAbstract
The concentrations of the oestrogen receptor (ER), and the mRNA levels of ERalpha, progesterone receptor (PR) and insulin-like growth factor I (IGF-I) were characterised in adrenal glands and uterine tissue of adult Corriedale sheep during the breeding season. The sheep were of different sex and gonadal status. Ewes had higher levels of cytosolic ER in the adrenals than the rams (mean +/- S.E.M.: 7.3 +/- 2.0 fmol/mg protein and 2.5 +/- 1.0 fmol/mg protein, respectively; P = 0.0091) and gonadectomy increased ER (mean +/- S.E.M.: 2.9 +/- 1.2 fmol/mg protein and 8.6 +/- 2.3 fmol/mg protein, intact and gonadectomised sheep, respectively; P = 0.0071). No differences could be observed in mRNA levels for ERalpha and IGF-I in the adrenal glands of all of the sheep. PR mRNA levels were reduced in ovariectomised ewes and enhanced in castrated rams (sex x gonadal status: P = 0.009). PR mRNA levels tended to be higher in ewes in the follicular phase than in ovariectomised ewes and intact rams (P < 0.1). All of the animals had positive nuclear staining for ERα in the adrenal cortex, but no differences were observed between the groups. In this study, we demonstrated the existence of ER in the adrenal gland of sheep and found varying sensitivity to oestrogens as the ER levels differed among sex and gonadal status. These findings indicate that oestrogens most likely affect steroidogenesis directly at the adrenal cortex and suggest that oestrogens are partly responsible for the sex differences in cortisol secretion in sheep. (C) 2003 Elsevier Inc. All rights reservedKeywords
Sheep; Adrenal gland; Oestrogen receptor; Sex differencesPublished in
Domestic Animal Endocrinology2003, volume: 25, number: 4, pages: 373-387
Publisher: ELSEVIER SCIENCE INC
Authors' information
Forsberg, Mats
Swedish University of Agricultural Sciences, Department of Biomedical Science and Veterinary Public Health
A., Bielli
E., van
L., Sahlin
S., Åkerberg
A., Meikle
UKÄ Subject classification
Veterinary Science
Animal and Dairy Science
Publication Identifiers
DOI: https://doi.org/10.1016/j.domaniend.2003.08.005
URI (permanent link to this page)
https://res.slu.se/id/publ/2609