Danik M, Chabot J G, Hassan-Gonzalez D, Suh M, Quirion R
Faculté des Etudes Supérieures, Université de Montréal, Québec, Canada.
J Comp Neurol. 1993 Aug 8;334(2):209-27. doi: 10.1002/cne.903340205.
Sulfated glycoprotein-2 (SGP-2) gene expression seems to be constitutively expressed in a variety of tissues and organs, although levels of expression vary widely from one tissue to the other. SGP-2, also known as clusterin, has been reported to be expressed in the central nervous system (CNS). Some possible roles for brain SGP-2 have been postulated. In order to provide a substrate for a better understanding of the functions of this glycoprotein in the CNS, we investigated the detailed anatomical and cellular distribution of SGP-2 mRNA in the adult rat brain as well as the variation in its cellular expression after excitotoxin lesion. Transcripts for SGP-2 were found to be distributed throughout the rat CNS, although regional differences in their prevalence were readily observed. The ependymal lining of the ventricles showed the highest level of expression followed by various gray matter areas, some of which contained very intensively labeled cells. These cells were mostly found among several hypothalamic and brainstem nuclei, the habenular complex, as well as in the ventral horn of the spinal cord, which displayed striking hybridization signals over motoneurons. Occasional cells expressing high levels of SGP-2 transcripts were found in fiber tracts. Highly SGP-2 mRNA-positive resting glial cells were mainly located near the glial limitans and blood vessels. Two areas of relatively low constitutive SGP-2 mRNA expression are shown to produce strong hybridization signals 10 days after the local administration of the excitotoxin kainic acid. This overexpression of SGP-2 transcripts appears to involve GFAP-positive cells. Taken together, these results indicate that in the intact adult rat CNS, various cell populations, including neurons, constitutively express SGP-2 transcripts, whereas in the injured brain, reactive astrocytes become the major producers.
硫酸化糖蛋白-2（SGP-2）基因表达似乎在多种组织和器官中持续存在，尽管不同组织间的表达水平差异很大。SGP-2，也被称为簇集素，据报道在中枢神经系统（CNS）中表达。人们推测了脑SGP-2的一些可能作用。为了更好地理解这种糖蛋白在中枢神经系统中的功能提供基础，我们研究了成年大鼠脑中SGP-2 mRNA的详细解剖学和细胞分布，以及兴奋性毒素损伤后其细胞表达的变化。虽然很容易观察到SGP-2转录本在大鼠中枢神经系统中的分布存在区域差异，但发现其转录本遍布整个大鼠中枢神经系统。脑室的室管膜衬里显示出最高水平的表达，其次是各种灰质区域，其中一些区域含有标记非常强烈的细胞。这些细胞大多位于几个下丘脑和脑干核、缰核复合体以及脊髓腹角中，在运动神经元上显示出明显的杂交信号。在纤维束中偶尔发现表达高水平SGP-2转录本的细胞。高度SGP-2 mRNA阳性的静息胶质细胞主要位于胶质界膜和血管附近。在局部注射兴奋性毒素红藻氨酸10天后，两个组成性SGP-2 mRNA表达相对较低的区域显示出强烈的杂交信号。SGP-2转录本的这种过表达似乎涉及GFAP阳性细胞。综上所述，这些结果表明，在完整的成年大鼠中枢神经系统中，包括神经元在内的各种细胞群体持续表达SGP-2转录本，而在受损的脑中，反应性星形胶质细胞成为主要的产生者。
