Ryan M C, Gundlach A L
University of Melbourne, Department of Medicine, Austin Hospital, Heidelberg, Australia.
J Comp Neurol. 1995 May 29;356(2):168-82. doi: 10.1002/cne.903560204.
Atrial natriuretic peptide (ANP) is one of three structurally homologous natriuretic peptides present in heart and brain, which is thought to be involved in the regulation of water and salt intake, blood pressure, and hormone secretion. In the present study, the distribution of preproatrial natriuretic peptide (ppANP) mRNA in the central nervous system of the rat was examined by in situ hybridisation histochemistry by using [35S]-labelled oligonucleotides. Cells expressing ppANP mRNA were apparent in several major neuronal systems, being present in hypothalamic, limbic, pontine and forebrain olfactory regions. Relatively high densities of ppANP mRNA-positive neurones were found in the anterior medial preoptic hypothalamic nucleus, medial habenular nucleus, and in Barrington's nucleus in the pons. Moderate numbers of ppANP mRNA-positive cells were present in a number of amygdaloid nuclei, including the posterolateral and anterior cortical nuclei, in the zona incerta, and the pedunculopontine tegmental nucleus. Other areas, including the ventromedial hypothalamic nucleus and the laterodorsal tegmental nucleus, displayed only low densities of ppANP mRNA-positive neurones. A number of structures in which ppANP mRNA (or ANP-like immunoreactivity) has not previously been reported were found to contain moderate to high numbers of ppANP mRNA-positive neurones including several nuclei associated with the olfactory system, such as the anterior olfactory nucleus and neurones of the tenia tecta and ventrolateral orbital cortex. Although ppANP mRNA in CA1 pyramidal cells of the hippocampus has been described, we also detected labelling in CA2 and ventral CA3 regions of the hippocampus. Conversely, nuclei such as the bed nucleus of the stria terminalis and the nucleus of the solitary tract, which are reported to possess ANP-like immunoreactivity, were found not to contain ppANP mRNA. Overall, these results demonstrate the presence of ANP gene expression in discrete neuronal populations of the rat central nervous system and provide additional evidence to support a putative role for this peptide in regulating and integrating hypothalamic, olfactory, limbic, and neuroendocrine systems.
心房利钠肽（ANP）是存在于心脏和大脑中的三种结构同源的利钠肽之一，被认为参与水盐摄入、血压和激素分泌的调节。在本研究中，通过使用[35S]标记的寡核苷酸，采用原位杂交组织化学方法检测大鼠中枢神经系统中前心房利钠肽（ppANP）mRNA的分布。表达ppANP mRNA的细胞在几个主要的神经元系统中明显可见，存在于下丘脑、边缘系统、脑桥和前脑嗅觉区域。在视前内侧下丘脑前核、内侧缰核和脑桥的巴林顿核中发现了相对高密度的ppANP mRNA阳性神经元。在一些杏仁核中存在中等数量的ppANP mRNA阳性细胞，包括后外侧和前皮质核、未定带和脚桥被盖核。其他区域，如下丘脑腹内侧核和背外侧被盖核，仅显示低密度的ppANP mRNA阳性神经元。一些以前未报道过含有ppANP mRNA（或ANP样免疫反应性）的结构被发现含有中等至大量的ppANP mRNA阳性神经元，包括几个与嗅觉系统相关的核，如前嗅核以及终纹床核和腹外侧眶皮质的神经元。虽然已经描述了海马CA1锥体细胞中的ppANP mRNA，但我们也在海马的CA2和腹侧CA3区域检测到了标记。相反，据报道具有ANP样免疫反应性的终纹床核和孤束核等核，被发现不含有ppANP mRNA。总体而言，这些结果证明了大鼠中枢神经系统离散神经元群体中存在ANP基因表达，并提供了额外的证据来支持该肽在调节和整合下丘脑、嗅觉、边缘系统和神经内分泌系统中的假定作用。
