Tolcos Mary, Tikellis Christos, Rees Sandra, Cooper Mark, Wookey Peter
Department of Medicine, University of Melbourne, Heidelberg West, Victoria 3081, Australia.
J Comp Neurol. 2003 Jan 27;456(1):29-38. doi: 10.1002/cne.10478.
In this study, the expression of receptors for calcitonin (CTR), the CTR C1a and C1b isoforms, was investigated during development of the fetal rat central nervous system (CNS) by using in situ hybridization and immunohistochemistry. Coincident expression with both techniques was evident. Immunohistochemical evidence for the expression of the C1a isoform alone was found. Expression was first observed at embryonic day 12/13 (E12/E13) within and adjacent to the ventricular zones known to include primary matrices of proliferation, in regions of the preoptic area, anterior and posterior hypothalamus, anterior and posterior pons, medulla, and spinal cord. At later times, with the decline in the density of immunoreactivity at these loci (E15), expression in primary matrices was found later at distinct loci within the ventricular zones of cerebellum (E17), and at E19, the tectum, lateral ventricle, and cortical subplate. By E19, the density of staining had increased and was widespread throughout the expanding CNS. In the rostral domains, moderate to high density was found in the external plexiform layer; the medial preoptic area and nucleus; the ventromedial, dorsomedial, and arcuate hypothalamic nuclei; and the lateral and posterior hypothalamic areas. In the midbrain, similar levels of expression were noted in the central nucleus of raphe; the deep mesencephalic, dorsal raphe, and laterodorsal tegmental nuclei; and the ventral periaqueductal gray. In the pons, positive loci included the locus coeruleus and the gigantocellular and pontine reticular nuclei. In the medulla, high expression was evident in the gigantocellular, intermediate, magnocellular, and medullary reticular, spinal trigeminal and cuneate nuclei; and the nucleus tractus solitarius. In the spinal cord, moderate to high density of staining was found in the ventral, dorsal, and lateral horns, and in the ventral, dorsal, and cuneate funiculi. On the other hand, transitory expression was found in the diagonal band, bed nucleus of the stria terminalis, amygdala, and the lateral mamillary and anterobasal nuclei of the hypothalamus. These studies indicate a role for CTR in the activation of some premigratory neuroblasts in the CNS as well as a possible role later in an undefined function associated with mature neurons of particular nuclei.
在本研究中，通过原位杂交和免疫组织化学方法，对大鼠胎儿中枢神经系统（CNS）发育过程中降钙素受体（CTR）及其C1a和C1b亚型的表达进行了研究。两种技术的表达结果一致。发现了仅C1a亚型表达的免疫组织化学证据。表达首先在胚胎第12/13天（E12/E13）于已知包含增殖初级基质的脑室区及其附近观察到，位于视前区、下丘脑前区和后区、脑桥前区和后区、延髓和脊髓区域。在稍后阶段，随着这些位点免疫反应密度的下降（E15），在小脑脑室区的不同位点（E17）以及E19时的顶盖、侧脑室和皮质下板中发现了初级基质中的表达。到E19时，染色密度增加并广泛分布于不断扩展的中枢神经系统中。在 Rostral 区域，在外部丛状层、内侧视前区和核、腹内侧、背内侧和弓状下丘脑核以及外侧和下丘脑后区发现了中度至高密度。在中脑，在中缝中央核、中脑深部、背侧中缝和外侧背侧被盖核以及腹侧导水管周围灰质中观察到类似的表达水平。在脑桥，阳性位点包括蓝斑以及巨细胞和脑桥网状核。在延髓，在巨细胞、中间、大细胞和延髓网状、脊髓三叉神经和楔束核以及孤束核中高表达明显。在脊髓中，在腹角、背角和侧角以及腹索、背索和楔束中发现了中度至高密度的染色。另一方面，在斜带、终纹床核、杏仁核以及下丘脑的外侧乳头体和前基底核中发现了短暂表达。这些研究表明CTR在中枢神经系统中某些迁移前神经母细胞的激活中起作用，以及在稍后与特定核的成熟神经元相关的未定义功能中可能起作用。
