Differential expression patterns of mRNAs for P2X receptor subunits in neurochemically characterized dorsal root ganglion neurons in the rat
Differential expression patterns of mRNAs for P2X receptor subunits in neurochemically characterized dorsal root ganglion neurons in the rat
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DOI：
10.1002/cne.20393
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发表时间：
2005-01-24
影响因子：
2.5
通讯作者：
Noguchi, K
中科院分区：
文献类型：
--
作者：
Kobayashi, K;Fukuoka, T;Noguchi, K
嗜离子嘌呤受体，即P2X受体，由多个P2X亚基组成。目前已克隆出7个亚基，命名为“P2X1-7”。我们使用核探针原位杂交组织化学（ISHH）检测了这些亚基mrna在大鼠腰背根神经节（DRG）中的精确分布，并通过ISHH和免疫组织化学表征了它们在一些神经元亚群中的表达。P2X1在DRG神经元中不表达。P2X2 mRNA在表达Ret的神经丝(NF)-200阴性小细胞神经元中优先表达，而在TrkA和TrkC mRNA中不优先表达。P2X3 mRNA主要在nf -200阴性神经元中表达。大多数p2x3阳性神经元存在Ret mRNA，其中约一半共表达TrkA和TRPV1 mRNA。P2X4是最普遍的亚基，均匀分布在所有被检查的神经元亚群中。约半数神经元表达P2X5和P2X6，且这些神经元大部分nf -200阳性。表达P2X7 mrna的神经元相当罕见。我们进一步检测了所有对P2X2-P2X6 mrna在DRG神经元中的共表达，发现：1)P2X4总是与其他亚基结合存在。2) TrkC神经元有P2X4、P2X5和P2X6三个亚基，占总神经元的32%。3) 12.5%的神经元同时存在P2X2和P2X3。4) 12.9%的神经元同时具有P2X3和P2X5。我们确定了P2X亚基在DRG中的神经元亚群特异性分布。这些发现提示DRG神经元中可能存在天然P2X受体亚基的组合。(C) 2004 Wiley-Liss, Inc。
The ionotropic purine receptors, P2X receptors, are composed of an assembly of multiple P2X subunits. At present, seven subunits have been cloned and named "P2X1-7." We examined the precise distribution of mRNAs for these subunits in the rat lumbar dorsal root ganglion (DRG) by in situ hybridization histochemistry (ISHH) using riboprobes and characterized their expression among some neuronal subpopulations by ISHH and immunohistochemistry. P2X1 was not expressed by DRG neurons. P2X2 mRNA was preferentially expressed by neurofilament (NF)-200 negative small-sized neurons expressing Ret, but not TrkA or TrkC mRNAs. P2X3 mRNA was mainly expressed by NF-200-negative neurons. Most P2X3-positive neurons had Ret mRNA, and about a half of them coexpressed TrkA and TRPV1 mRNAs. P2X4 was the most ubiquitous subunit, evenly distributing among all examined neuronal subpopulations. P2X5 and P2X6 were expressed by about half of the neurons, and most of these neurons were NF-200-positive. P2X7 mRNA-expressing neurons were quite rare. We further examined the coexpression of all pairs of P2X2-P2X6 mRNAs in DRG neurons and found that: 1) P2X4 was always present in combination with the other subunits. 2) All TrkC neurons had three subunits, P2X4, P2X5, and P2X6, and made up 32% of the total neurons. 3) 12.5% of the total neurons had both P2X2 and P2X3. 4) 12.9% of the neurons had both P2X3 and P2X5. We determined the neuronal subpopulation-specific distribution of P2X subunits in the DRG. These findings suggest possible combinations of subunits of native P2X receptor in DRG neurons. (C) 2004 Wiley-Liss, Inc.