Rogers J H, Hunt S P
MRC Laboratory of Molecular Biology, Cambridge, U.K.
Neuroscience. 1987 Oct;23(1):343-61. doi: 10.1016/0306-4522(87)90295-8.
The enzyme carbonic anhydrase is widespread in brain tissue. In rodent brains it has been reported to be exclusively in oligodendroglia but there has been some debate about the generality of this finding. To investigate the cellular distribution of carbonic anhydrase by an independent technique, we have examined the chick brain by in situ hybridization to detect mRNA from the carbonic anhydrase-II gene, using as controls the actin and vimentin genes. The most intense carbonic anhydrase-II hybridization is to the choroid plexus, to the Bergmann glia of the cerebellum, and to the Müller cells in the retina. Elsewhere, some brain regions are negative while others show many individual strongly positive cells; carbonic anhydrase-II mRNA is particularly abundant in some parts of the hyperstriatum, tectum and thalamus. Some of the larger labelled cells are identifiable as neurons. By histochemistry, we confirm the presence of the carbonic anhydrase enzyme in choroid plexus and Bergmann glia, but the enzyme is also present in blood vessel walls where there is no carbonic anhydrase-II mRNA; this may be a different isozyme. During embryogenesis, carbonic anhydrase-II mRNA appears in the retina as early as two days of incubation, but does not appear in the brain until much later.
碳酸酐酶在脑组织中广泛存在。在啮齿动物脑中，据报道它仅存在于少突胶质细胞中，但这一发现的普遍性存在一些争议。为了通过一种独立技术研究碳酸酐酶的细胞分布，我们通过原位杂交检测碳酸酐酶-II基因的mRNA来检查鸡脑，同时以肌动蛋白和波形蛋白基因作为对照。碳酸酐酶-II杂交最强烈的部位是脉络丛、小脑的伯格曼胶质细胞以及视网膜中的米勒细胞。在其他地方，一些脑区呈阴性，而另一些则显示许多单个的强阳性细胞；碳酸酐酶-II mRNA在纹状体、顶盖和丘脑的某些部位特别丰富。一些较大的标记细胞可被识别为神经元。通过组织化学方法，我们证实脉络丛和伯格曼胶质细胞中存在碳酸酐酶，但在没有碳酸酐酶-II mRNA的血管壁中也存在该酶；这可能是一种不同的同工酶。在胚胎发育过程中，碳酸酐酶-II mRNA早在孵化两天时就出现在视网膜中，但直到很久以后才出现在脑中。
