Imbe Hiroki, Okamoto Keiichiro, Kadoya Toshihiko, Horie Hidenori, Senba Emiko
Department of Anatomy and Neurobiology, Wakayama Medical University, Kimiidera 811-1, Wakayama 640-0012, Japan.
Brain Res. 2003 Dec 12;993(1-2):72-83. doi: 10.1016/j.brainres.2003.08.064.
Galectin-1 is one of the endogenous-galactoside-binding lectins, suggested to be involved in a variety of functions, such as neurite outgrowth, synaptic connectivity, cell proliferation and apoptosis. This protein is expressed in the dorsal root ganglion (DRG) and the spinal cord in the developing and adult rats, especially intensely in small DRG neurons. In the present study, we examined whether galectin-1 is colocalized with TrkA or c-Ret mRNA in small DRG neurons and the effect of axotomy on the expression of galectin-1 in the spinal cord. About 20% of the DRG neurons showed intense galectin-1-immunoreactivity (IR). Of the intensely galectin-1-IR DRG neurons, 93.9% displayed c-Ret mRNA positive signals. On the other hand, only 6.8% displayed TrkA mRNA positive signals. Galectin-1-IR was increased in the dorsal horn at 1 to 2 weeks after axotomy. Intrathecal administration of anti-recombinant human galectin-1 antibody (anti-rhGAL-1 Ab) partially but significantly attenuated the upregulation of substance P receptor (SPR) in the spinal dorsal horn and the mechanical hypersensitivity induced by the peripheral nerve injury. These data suggest that endogenous galectin-1 may potentiate neuropathic pain after the peripheral nerve injury at least partly by increasing SPR in the dorsal horn.
半乳糖凝集素-1是一种内源性半乳糖苷结合凝集素，被认为参与多种功能，如神经突生长、突触连接、细胞增殖和凋亡。这种蛋白质在发育中和成年大鼠的背根神经节（DRG）和脊髓中表达，在小DRG神经元中表达尤为强烈。在本研究中，我们检测了半乳糖凝集素-1在小DRG神经元中是否与TrkA或c-Ret mRNA共定位，以及轴突切断对脊髓中半乳糖凝集素-1表达的影响。约20%的DRG神经元显示强烈的半乳糖凝集素-1免疫反应性（IR）。在强烈半乳糖凝集素-1-IR的DRG神经元中，93.9%显示c-Ret mRNA阳性信号。另一方面，只有6.8%显示TrkA mRNA阳性信号。轴突切断后1至2周，背角的半乳糖凝集素-1-IR增加。鞘内注射抗重组人半乳糖凝集素-1抗体（抗-rhGAL-1 Ab）部分但显著减弱了脊髓背角中P物质受体（SPR）的上调以及外周神经损伤诱导的机械性超敏反应。这些数据表明，内源性半乳糖凝集素-1可能至少部分通过增加背角中的SPR来增强外周神经损伤后的神经性疼痛。
