背根神经节内代谢型谷氨酸受体2与酸敏感性离子通道3和辣椒素受体1的共存研究(英文)  

Co-localization of metabotropic glutamate receptor 2 with ASIC3 or TRPV1 in the dorsal root ganglion of rat

作　　者：张婷[1] 王旭翾[2] 张靖[3] 史娟[1] 李会莉[1] 李云庆[1] 

机构地区：[1]第四军医大学人体解剖学与组织胚胎学教研室,西安710032 [2]第四军医大学2004级口腔医学系本科学员队,西安710032 [3]中国科学院心理所行为遗传研究中心,北京100101

出　　处：《神经解剖学杂志》2008年第6期575-580,共6页Chinese Journal of Neuroanatomy

基　　金：国家自然科学基金(No.30500154,30871004)资助项目

摘　　要：代谢型谷氨酸受体(mGluR)2/3在伤害性信息从外周向脊髓传递的过程中发挥着重要作用。以往研究证明在大鼠中mGluR2参与了机械性超敏和热超敏的形成,因此本研究拟采用免疫荧光组织化学染色技术揭示背根节(DRG)中mGluR2和酸敏感性离子通道3(ASIC3),一个多觉机械性感受器,或者和热伤害性感受器辣椒素受体(TRPV1)的共存情况。结果显示:mGluR2主要存在于DRG神经元的胞浆中。计数结果显示DRG中35.85%的神经元呈mGluR2免疫阳性。在这些阳性神经元中,82.61%为小细胞(直径小于30μm);5.79%为中等细胞(直径为30～50μm);11.59%为大细胞(直径大于50μm)。进一步在免疫荧光双重标记切片上可观察到分别有42.45%和79.78%的小型mGluR2阳性神经元同时表达ASIC3或TRPV1免疫阳性。以上结果提示mGluR2主要存在于DRG中的小神经元中,这些神经元通常被认为是外周Aδ-或C-纤维传入的伤害性感觉神经元,在这类神经元中mGluR2与ASIC3或TRPV1均有大量共存,提示这些共存可能与机械性或热超敏的产生或者维持有着重要的联系。Metabotropic glutamate receptor （mGluR） 2/3 plays an important role on the nociceptive transmission from periphery to spinal cord. The previous studies demonstrated that mGluR2 can contribute to mechanical hypersensitivity and thermal hypersensitivity in rat. Therefore, in the present study, by using the immunofluorescence histochemical technique, we try to explore that whether mGluR2 is colocalized with acid-sensing ion channel 3 （ ASIC3 ）, a multi-modulator of mechanosensation, or transient receptor potential/vanilloid receptor subtype-1 （TRPV1）, which responses for thermosensation in dorsal root ganglion （DRG）. Morphological observations showed that mGluR2-immunoreactivity was mainly distributed in cellular plasma of neurons in DRG. The counting number results indicated that 35. 84% of DRG neurons were mGluR2-immunoreactive （it）. On the other hand, 82.61% of mGluR2-ir cells were the small-diameter neurons （ diameter： 〈 30 μm）, 5.79% of which were the medium-diameter neurons （ diameter： 30 - 50 μm） and 11.59% of which was the large-diameter neurons （ diameter： 〉 50 μm）. Furthermore, 42.45 % and 79.78 % of mGluR2-ir cells was individually co-localized with ASIC3- or TRPV1-ir in small-diameter neurons in the double-labeled immunofluorescence sections. The present results suggest that mGluR2 mainly exists in small neurons of the DRG, which are regarded as nociceptors consisting of Aδ- and C-fibers. While mGluR2 is highly co-localized with ASIC3 and TRPV1, implying their potential relationship in DRG may be involved in mechanical hypersensitivity and thermal hypersensitivity.

关 键 词：代谢型谷氨酸受体2 酸敏感性离子通道3 辣椒素受体1 背根节 大鼠 

分 类 号：R33[医药卫生—人体生理学]