Accepted Preprint first posted online on 27 May 2009
Journal of Endocrinology 2009;202:279.
Journal of Endocrinology (2009) In press
DOI: 10.1677/JOE-09-0175
© 2009 Society for Endocrinology
Reversal of the hypothalamo-pituitary-adrenal response to oestrogens around puberty
Obaro Evuarherhe,
James Leggett,
Eleanor Waite,
Yvonne Kershaw and
Stafford Lightman
O Evuarherhe, HW LINE, University of Bristol, Bristol, BS1 3NY, United Kingdom
J Leggett, HW LINE, University of Bristol, Bristol, United Kingdom
E Waite, HW LINE, University of Bristol, Bristol, United Kingdom
Y Kershaw, HW LINE, University of Bristol, Bristol, United Kingdom
S Lightman, HW LINE, University of Bristol, Bristol, United Kingdom
Correspondence: Obaro Evuarherhe, Email: obaro.evuarherhe{at}bristol.ac.uk
The neuroendocrine gender-dimorphism which begins during perinatal development is completed during puberty. We have previously described how perinatal gonadal steroids programme HPA activity in adulthood and we now assess the role of peripubertal ovarian hormones. Prepubertal females were treated subcutaneously with either cholesterol or 17β-oestradiol and their pituitary-adrenal activity was assessed 5 days later. Oestradiol suppressed the ACTH and corticosterone responses to restraint stress in the prepubertal female. Further groups of female rats were ovariectomized either before or after puberty and adult animals were subsequently treated with subcutaneous implants containing either 17β-oestradiol or cholesterol. Corticosterone pulsatility was assessed using an automated blood sampling system to collect blood from freely moving animals at 10-min intervals over 24 hours. Oestradiol administered to adults that had been ovariectomized either pre- or post-pubertally displayed a significantly higher mean corticosterone level as well as increased pulse frequency and pulse amplitude compared to cholesterol treated controls. These data demonstrate a reversal in the effect of oestrogens on HPA axis activity over the time of puberty with inhibitory effects prepubertally and stimulatory actions after puberty and imply an ovarian steroid independent mechanism of pubertal maturation of HPA sensitivity to oestrogens.
Copyright © 2009 by the Society for Endocrinology.