da Costa A P, Ma X, Ingram C D, Lightman S L, Aguilera G
Section of Endocrine Physiology, NICHD, NIH, Bethesda, MD 20892, USA.
Brain Res Mol Brain Res. 2001 Jul 13;91(1-2):119-30. doi: 10.1016/s0169-328x(01)00137-1.
This study investigated the expression of corticotropin releasing hormone (CRH) and its receptor CRHR-1, and arginine vasopressin (AVP) mRNAs during the stress hyporesponsive periods of late pregnancy and lactation (day-3) and in virgin stress-responsive females. In situ hybridization histochemistry showed that basal CRH mRNA in the paraventricular nucleus (PVN) decreased in pregnant and increased in lactating rats (compared with virgin controls), whereas it increased after restraint stress only in virgin rats. Basal PVN CRHR-1 mRNA increased markedly in all groups but reached lower levels in pregnant rats. Basal AVP mRNA in the parvocellular PVN was higher in lactating rats, and in contrast to CRH mRNA, it increased after stress in all groups. In medial preoptic area (MPOA) CRH mRNA levels were higher in lactating females compared with virgin and pregnant rats, and unexpectedly they decreased markedly after stress only in virgin rats. CRH mRNA levels in the central and medial nuclei of the amygdala were higher in lactating rats than in virgin or pregnant ones, and stress had no effect in either group. These data suggest that these stress hyporesponsive periods: (1) do not depend on basal CRH mRNA expression in the PVN; (2) appear to have intact stress-activated afferent pathways to the PVN, as shown by preservation of CRHR-1 and AVP responses to stress, but the information may be differently processed; (3) are associated with an alteration in a CRH mediated pathway from the MPOA.
本研究调查了促肾上腺皮质激素释放激素(CRH)及其受体CRHR - 1,以及精氨酸加压素(AVP)mRNA在妊娠晚期和哺乳期(第3天)应激低反应期和未孕应激反应性雌性动物中的表达。原位杂交组织化学显示,室旁核(PVN)中的基础CRH mRNA在妊娠大鼠中降低,而在泌乳大鼠中升高(与未孕对照相比),而仅在未孕大鼠中,束缚应激后其升高。基础PVN CRHR - 1 mRNA在所有组中均显著增加,但在妊娠大鼠中达到较低水平。小细胞PVN中的基础AVP mRNA在泌乳大鼠中较高,与CRH mRNA相反,所有组在应激后其均增加。与未孕和妊娠大鼠相比,泌乳雌性动物内侧视前区(MPOA)中的CRH mRNA水平较高,且意外的是,仅在未孕大鼠中应激后其显著降低。杏仁核中央核和内侧核中的CRH mRNA水平在泌乳大鼠中高于未孕或妊娠大鼠,且应激对两组均无影响。这些数据表明,这些应激低反应期:(1)不依赖于PVN中的基础CRH mRNA表达;(2)似乎具有完整的通向PVN的应激激活传入通路,如CRHR - 1和AVP对应激的反应得以保留所示,但信息可能以不同方式处理;(3)与MPOA中CRH介导的通路改变有关。