大鼠背根神经节肽能和非肽能小型神经元均表达GABA_B受体——脊髓水平突触前痛觉调节机制的证据(英文)

BOTH PEPTIDERGIC AND NONPEPTIDERGIC SMALL NEURONS IN RAT DRG EXPRESS GABA_BR EVIDENCE FOR PAIN REGULATION BY PRESYNAPTIC MECHANISM IN SPINAL LEVEL

已知痛觉传递调制途径之一是通过背根神经节中的小型神经元的突触前代谢型GABAB受体介导。为了探讨肽能和非肽能2个亚群的小型背根神经节(DRG)神经元是否在痛觉调制过程中发挥同等作用,本实验用免疫荧光组织化学法和激光共聚焦显微镜技术观察了DRG内肽能和非肽能2个亚群的小型神经元中GABAB受体的表达。结果显示:92%的肽能和90%的非肽能亚群的小型神经元均表达GABAB受体,这些受体存在于2个亚群的胞体及其分布在脊髓背角特定板层的中枢突中。该结果表明在痛觉调制过程中,肽能和非肽能2个亚群的小型DRG内神经元在脊髓水平发挥类似作用,但作用于脊髓背角的不同板层。

It has been reported that the small type of neurons in the dorsal root ganglion （DRG） play an important role in pain regulation by a presynaptic mechanism via the metabetropic typo-B γ-aminobutyric acid receptors （ GABABR ）. In order to understand whether the 2 populations of the small type of the neurons, peptidergic and nonpeptidergic, in DRG share the same role, immunofloureseent histochemical methods and confocal laser scanning microscope were employed to investigate the expression of the GABABR in the poptidergic and nonpoptidergic small DRG neurons. The results revealed that 92% of the poptiderglc and 90% of nonpeptidergic small DRG neurons express GABABR in their perikarya and central processes, which distribute in the various laminae of the spinal dorsal horn. These results suggest both the peptidergic and nonpoptidergie populations of the small neurons in the DRG share similar role in pain modulation via presynaptic mechanisms but in given laminae of the spinal dorsal horn.