Jégou Sylvie, Cartier Dorthe, Dubessy Christophe, Gonzalez Bruno J, Chatenet David, Tostivint Hervé, Scalbert Elizabeth, LePrince Jérome, Vaudry Hubert, Lihrmann Isabelle
Institut National de la Santé et de la Recherche Médicale U-413, Laboratory of Cellular and Molecular Neuroendocrinology, European Institute for Peptide Research (IFRMP23), University of Rouen, 76821 Mont-Saint-Aignan, France.
J Comp Neurol. 2006 Mar 1;495(1):21-36. doi: 10.1002/cne.20845.
The vasoactive peptide urotensin II (UII) is primarily expressed in motoneurons of the brainstem and spinal cord. Intracerebroventricular injection of UII provokes various behavioral, cardiovascular, motor, and endocrine responses in the rat, but the distribution of the UII receptor in the central nervous system (CNS) has not yet been determined. In the present study, we have investigated the localization of UII receptor (GPR14) mRNA and UII binding sites in the rat CNS. RT-PCR analysis revealed that the highest density of GPR14 mRNA occurred in the pontine nuclei. In situ hybridization histochemistry showed that the GPR14 gene is widely expressed in the brain and spinal cord. In particular, a strong hybridization signal was observed in the olfactory system, hippocampus, olfactory and medial amygdala, hypothalamus, epithalamus, several tegmental nuclei, locus coeruleus, pontine nuclei, motor nuclei, nucleus of the solitary tract, dorsal motor nucleus of the vagus, inferior olive, cerebellum, and spinal cord. Autoradiographic labeling of brain slices with radioiodinated UII showed the presence of UII-binding sites in the lateral septum, bed nucleus of the stria terminalis, medial amygdaloid nucleus, anteroventral thalamus, anterior pretectal nucleus, pedunculopontine tegmental nucleus, pontine nuclei, geniculate nuclei, parabigeminal nucleus, dorsal endopiriform nucleus, and cerebellar cortex. Intense expression of the GPR14 gene in some hypothalamic nuclei (supraoptic, paraventricular, ventromedian, and arcuate nuclei), in limbic structures (amygdala and hippocampus), in medullary nuclei (solitary tract, dorsal motor nucleus of the vagus), and in motor control regions (cerebral and cerebellar cortex, substantia nigra, pontine nuclei) provides the anatomical substrate for the central effects of UII on behavioral, cardiovascular, neuroendocrine, and motor functions. The occurrence of GPR14 mRNA in cranial and spinal motoneurons is consistent with the reported autocrine/paracrine action of UII on motoneurons.
血管活性肽尾加压素II（UII）主要表达于脑干和脊髓的运动神经元。脑室内注射UII可在大鼠中引发各种行为、心血管、运动和内分泌反应，但UII受体在中枢神经系统（CNS）中的分布尚未确定。在本研究中，我们调查了大鼠CNS中UII受体（GPR14）mRNA和UII结合位点的定位。逆转录聚合酶链反应（RT-PCR）分析显示，GPR14 mRNA密度最高的部位是脑桥核。原位杂交组织化学表明，GPR14基因在脑和脊髓中广泛表达。特别是，在嗅觉系统、海马、嗅觉和内侧杏仁核、下丘脑、上丘脑、几个被盖核、蓝斑、脑桥核、运动核、孤束核、迷走神经背运动核、下橄榄核、小脑和脊髓中观察到强烈的杂交信号。脑片用放射性碘化UII进行放射自显影标记显示，在外侧隔、终纹床核、内侧杏仁核、丘脑前腹核、前顶盖前核、脚桥被盖核、脑桥核、膝状核、副视束核、背内梨状核和小脑皮质中存在UII结合位点。GPR14基因在一些下丘脑核（视上核、室旁核、腹内侧核和弓状核）、边缘结构（杏仁核和海马）、延髓核（孤束核、迷走神经背运动核）以及运动控制区域（大脑和小脑皮质、黑质、脑桥核）中的强烈表达为UII对行为、心血管、神经内分泌和运动功能的中枢作用提供了解剖学基础。GPR14 mRNA在颅神经和脊髓运动神经元中的出现与报道的UII对运动神经元的自分泌/旁分泌作用一致。
