Denial or receipt of expected reward through maternal contact during the neonatal period differentially affect the development of the rat amygdala and program its function in adulthood in a sex-dimorphic way

PSYCHONEUROENDOCRINOLOGY

卷:38

Article

Diamantopoulou, Anastasia¹  Raftogianni, Androniki¹  Stamatakis, Antonios¹  Tzanoulinou, Stamatina¹  Oitzl, Melly S.²  Stylianopoulou, Fotini¹ 

[1] Univ Athens, Lab Biol Biochem, Fac Nursing, GR-11527 Athens, Greece

[2] Leiden Univ, Div Med Pharmacol, Leiden, Netherlands

关键词: Amygdala;    c-Fos;    Corticosterone;    Fear conditioning;    Sex differences;    Neonates;    Early life experiences;    Maternal care;   

DOI  :  10.1016/j.psyneuen.2013.02.012

来源: Elsevier

【 摘 要 】

Early experiences affect brain development and thus adult brain function and behavior. We employed a novel early experience model involving denial (DER) or receipt of expected reward (RER) through maternal contact in a T-maze. Exposure to the DER experience for the first time, on postnatal day 10 (PND10), was stressful for the pups, as assessed by increased corticosterone levels, and was accompanied by enhanced activation of the amygdala, as assessed by c-Fos immunohistochemistry. Re-exposure to the same experience on days 11-13 led to adaptation. Corticosterone levels of the RER pups did not differ on the first and last days of training (PND10 and 13 respectively), while on PND11 and 12 they were lower than those of the CTR. The RER experience did not lead to activation of the amygdala. Males and females exposed as neonates to the DER or RER experience, and controls were tested as adults in the open field task (OF), the elevated plus maze (EPM), and cued and contextual fear conditioning (FC). No group differences were found in the EPM, while in the OF, both male and female DER animals, showed increased rearings, compared to the controls. In the FC, the RER males had increased memory for both context and cued conditioned fear, than either the DER or CTR. On the other hand, the DER males, but not females showed an increased activation, as assessed by c-Fos expression, of the amygdala following fear conditioning. Our results show that the DER early experience programmed the function of the adult amygdala as to render it more sensitive to fearful stimuli. This programming by the DER early experience could be mediated through epigenetic modifications of histones leading to chromatin opening, as indicated by our results showing increased levels of phospho-acetyl-histone-3 in the amygdala of the DER males. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

Free