Driessen Terri M, Zhao Changjiu, Whittlinger Anna, Williams Horecia, Gammie Stephen C
Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.
Department of Animal Science, Fort Valley State University, Fort Valley, Georgia, United States of America.
PLoS One. 2014 Jan 8;9(1):e83098. doi: 10.1371/journal.pone.0083098. eCollection 2014.
Neurotensin (NT) is a neuropeptide identical in mice and humans that is produced and released in many CNS regions associated with maternal behavior. NT has been linked to aspects of maternal care and previous studies have indirectly suggested that endogenous NT signaling is altered in the postpartum period. In the present study, we directly examine whether NT and its receptors exhibit altered gene expression in maternal relative to virgin outbred mice using real time quantitative PCR (qPCR) across multiple brain regions. We also examine NT protein levels using anti-NT antibodies and immunohistochemistry in specific brain regions. In the medial preoptic area (MPOA), which is critical for maternal behaviors, mRNA of NT and NT receptor 3 (Sort1) were significantly up-regulated in postpartum mice compared to virgins. NT mRNA was also elevated in postpartum females in the bed nucleus of the stria terminalis dorsal. However, in the lateral septum, NT mRNA was down-regulated in postpartum females. In the paraventricular nucleus of the hypothalamus (PVN), Ntsr1 expression was down-regulated in postpartum females. Neurotensin receptor 2 (Ntsr2) expression was not altered in any brain region tested. In terms of protein expression, NT immunohistochemistry results indicated that NT labeling was elevated in the postpartum brain in the MPOA, lateral hypothalamus, and two subregions of PVN. Together, these findings indicate that endogenous changes occur in NT and its receptors across multiple brain regions, and these likely support the emergence of some maternal behaviors.
神经降压素（NT）是一种在小鼠和人类中相同的神经肽，在许多与母性行为相关的中枢神经系统区域产生和释放。NT与母性关怀的各个方面有关，先前的研究间接表明产后内源性NT信号会发生改变。在本研究中，我们使用实时定量PCR（qPCR）直接检测在多个脑区中，与未生育的远交系小鼠相比，NT及其受体在母鼠中是否表现出基因表达的改变。我们还使用抗NT抗体和免疫组织化学方法检测特定脑区的NT蛋白水平。在对母性行为至关重要的内侧视前区（MPOA），与未生育小鼠相比，产后小鼠中NT和NT受体3（Sort1）的mRNA显著上调。产后雌性小鼠终纹床核背侧的NT mRNA也升高。然而，在外侧隔区，产后雌性小鼠的NT mRNA下调。在下丘脑室旁核（PVN），产后雌性小鼠的Ntsr1表达下调。在所检测的任何脑区中，神经降压素受体2（Ntsr2）的表达均未改变。在蛋白表达方面，NT免疫组织化学结果表明，MPOA、下丘脑外侧区和PVN的两个亚区中，产后大脑中的NT标记升高。总之，这些发现表明NT及其受体在多个脑区发生内源性变化，这可能支持了一些母性行为的出现。
