Ceccatelli S, Calzá L, Giardino L
Division of Toxicology, Karolinska Institute, Stockholm, Sweden.
Brain Res Mol Brain Res. 1996 Apr;37(1-2):175-80. doi: 10.1016/0169-328x(95)00304-b.
Hypothalamic corticotropin releasing hormone (CRH) controls the release of adrenocorticotrophic hormone (ACTH) from the pituitary and, and therefore has a major role in the activation of the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis function has been shown to be impaired in the neonatal period as well as in aging. Since corticotropin-releasing hormone receptor (CRHr) plays a crucial role in the regulation of HPA axis, using in situ hybridization histochemistry we have analyzed the rat pituitary for the presence of CRHr mRNA in the neonatal period and during aging. The results show an increase in CRHr mRNA in 3-day-old rats, with a progressive increase within the first month. In the aging rat, we observed a down-regulation of the CRHr mRNA localized in the anterior pituitary, gland viceversa, an increased signal in the intermediate lobe. Our findings demonstrate age-related changes in the expression of the CRHr mRNA in the pituitary, with a differential regulation in the anterior and intermediate lobes of aging rats.
下丘脑促肾上腺皮质激素释放激素（CRH）控制垂体中促肾上腺皮质激素（ACTH）的释放，因此在激活下丘脑-垂体-肾上腺（HPA）轴中起主要作用。已表明HPA轴功能在新生儿期以及衰老过程中会受损。由于促肾上腺皮质激素释放激素受体（CRHr）在HPA轴的调节中起关键作用，我们使用原位杂交组织化学分析了新生期和衰老过程中大鼠垂体中CRHr mRNA的存在情况。结果显示，3日龄大鼠的CRHr mRNA增加，在第一个月内逐渐增加。在衰老大鼠中，我们观察到位于垂体前叶的CRHr mRNA下调，反之，中间叶的信号增加。我们的研究结果表明垂体中CRHr mRNA的表达存在与年龄相关的变化，在衰老大鼠的前叶和中间叶中有不同的调节。
