Altered stress responsiveness and hypothalamic‐pituitary‐adrenal axis function in male rat offspring of socially isolated parents. (9th May 2013)

• Record Type: Journal Article
• Authors: Pisu, Maria Giuseppina; Garau, Anna; Olla, Pierluigi; Biggio, Francesca; Utzeri, Cinzia; Dore, Riccardo; Serra, Mariangela
• Is Part Of: Journal of neurochemistry. Volume 126:Number 4(2013:Aug.)
• Page Start: 493
• Page End: 502
• Publication Date: 2013-05-09
• Subjects: 3α, 5α‐tetrahydroprogesterone -- glucocorticoid receptor -- HPA axis -- rat -- socially isolated offspring -- stress; Neurochemistry -- Periodicals; 616.8042
• DOI: 10.1111/jnc.12273
• Languages: English
• ISSNs: 0022-3042

Abstract

Abstract: Social isolation in male rats at weaning results in reduced basal levels of the neuroactive steroid 3α, 5α‐tetrahydroprogesterone (3α, 5α‐TH PROG) in the brain and plasma as well as increased anxiety‐like behavior. We now show that socially isolated female rats also manifest a reduced basal cerebrocortical concentration of 3α, 5α‐TH PROG as well as an anxiety‐like profile in the elevated plus‐maze and Vogel conflict tests compared with group‐housed controls. In contrast, despite the fact that they were raised under normal conditions, adult male offspring of male and female rats subjected to social isolation before mating exhibited an increased basal cerebrocortical level of 3α, 5α‐TH PROG but no difference in emotional reactivity compared with the offspring of group‐housed parents. These animals also showed an increased basal activity of the hypothalamic‐pituitary‐adrenal axis as well as reduced abundance of corticotropin‐releasing factor in the hypothalamus and of corticotropin‐releasing factor receptor type 1 in the pituitary. Moreover, negative feedback regulation of hypothalamic‐pituitary‐adrenal axis activity by glucocorticoid was enhanced in association with up‐regulation of glucocorticoid receptor expression in the hippocampus. There was also attenuation of corticosterone release induced by foot‐shock stress in the offspring of socially isolated parents. The increase in the brain concentration of 3α, 5α‐TH PROG induced by acute stress was also blunted in these animals. Our results thus show that a stressful experience before mating can influence neuroendocrine signaling in the next generation. Abstract : Adult offspring of isolated rats exhibited an increased brain level of allopregnanolone, increased basal activity of the HPA axis, reduction of hypothalamic CRF and CRFR1 in the pituitary. There was also attenuation of corticosterone response by acute stress and up‐regulation of GR expression in the hippocampus. In conclusion, a stressful experience before mating influence neuroendocrine signalling in the next generation.