Abbadie C, Pan Y, Drake C T, Pasternak G W
The Laboratory of Molecular Neuropharmacology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY, USA.
Neuroscience. 2000;100(1):141-53. doi: 10.1016/s0306-4522(00)00248-7.
The present study examined immunohistochemically the CNS distributions of a splice variant of the mu-opioid receptor, MOR-1D, in both rats and mice. In MOR-1D, exon 4 of MOR-1 is replaced by two additional exons that code for seven amino acids. Using rabbit antisera, we compared immunohistochemically the regional distribution of a C-terminal epitope of MOR-1D to that of a C-terminal epitope from MOR-1 and a C-terminal epitope from another splice variant, MOR-1C. The general distribution of MOR-1D-like immunoreactivity was similar in both mouse and rat. MOR-1D-like immunoreactivity was seen in the dentate gyrus and in the mossy fibers of the hippocampal formation, the nucleus of the solitary tract and the area postrema, the inferior olivary nucleus, the nucleus ambiguous, the spinal trigeminal nucleus and the spinal cord. MOR-1D-like immunoreactivity was not observed in some regions containing dense MOR-1-like immunoreactivity, such as the striatum or the locus coeruleus. In regions containing MOR-1, MOR-1C and MOR-1D, the pattern of each variant was unique.MOR-1D and MOR-1C are splice variants of the cloned mu-opioid receptor MOR-1. Although they differ only at the tip of the carboxy terminus, they show marked differences in their regional distributions, as determined immunohistochemically by epitopes in their unique carboxy termini. Since the splice variants are derived from the same gene, these differences in regional distribution imply region-specific messenger RNA processing.
本研究采用免疫组织化学方法，检测了大鼠和小鼠中枢神经系统（CNS）中μ-阿片受体剪接变体MOR-1D的分布情况。在MOR-1D中，MOR-1的外显子4被另外两个编码7个氨基酸的外显子所取代。我们使用兔抗血清，通过免疫组织化学方法比较了MOR-1D的C末端表位与MOR-1的C末端表位以及另一种剪接变体MOR-1C的C末端表位的区域分布。MOR-1D样免疫反应性在小鼠和大鼠中的总体分布相似。在齿状回、海马结构的苔藓纤维、孤束核、最后区、下橄榄核、疑核、三叉神经脊束核和脊髓中可见MOR-1D样免疫反应性。在一些含有密集MOR-1样免疫反应性的区域，如纹状体或蓝斑，未观察到MOR-1D样免疫反应性。在同时含有MOR-1、MOR-1C和MOR-1D的区域，每种变体的模式都是独特的。MOR-1D和MOR-1C是克隆的μ-阿片受体MOR-1的剪接变体。尽管它们仅在羧基末端的尖端有所不同，但通过其独特羧基末端的表位进行免疫组织化学测定时，它们在区域分布上显示出明显差异。由于这些剪接变体来自同一基因，区域分布的这些差异意味着存在区域特异性的信使核糖核酸加工过程。
