摘要
目的:NMDA受体的NR1和NR2B亚基对于痛觉的产生和维持起着关键作用,本文旨在探究NMDA受体在大鼠睾丸痛模型中的表达及可能机制。方法:参照Yoshioka等的方法建立大鼠睾丸痛模型,分实验组和对照组,其中对照组大鼠睾丸注射0.2 ml生理盐水,实验组大鼠睾丸注射0.2 ml 2%醋酸溶液,后进行行为学检测。建模成功后4 h采用Western印迹、RT-qPCR、免疫荧光检测NMDA受体在背根神经节和脊髓背角中的表达。结果:建模后,实验组大鼠逃避反应潜伏期明显降低,于4 h达到最低值[(4.15±0.84) s],显著低于对照组[(12.32±1.05) s,P<0.05]。建模后4 h,RT-qPCR, Western印迹、免疫荧光结果显示:与对照组相比,实验组大鼠背根神经节中NR2B mRNA和蛋白表达明显升高(P<0.05),脊髓背角中NR2B的表达无明显变化;实验组和对照组大鼠的背根神经节和脊髓背角的NR1表达也无明显差异。结论:NMDA受体在大鼠睾丸痛发病过程中具有重要作用,疼痛前期便可通过上调NMDA受体NR2B亚基表达介导外周痛敏形成,介导睾丸疼痛的发生。
Objective: To explore the expression of the N-methyl-D-aspartate( NMDA) receptor in the rat model of orchialgia and its possible mechanisms. Methods: According to Yoshioka's method,the male rats in the control group were injected with 0. 2 ml saline,and those in the experimental group with 0. 2 ml 2% acetic acid solution. Then we tested the behavioral responses of the rats and determined the expressions of the subunits NR1 and NR2 B of the NMDA receptor in the dorsal root ganglion and spinal dorsal horn by Western blot,RT-qP CR and immunofluorescence staining. Results: The withdrawal latency was decreased in the model rats,reaching the lowest value at 4 hours after modeling,significantly lower than in the controls( [4. 15 ± 0. 84] vs [12. 32 ± 1. 05],P< 0. 05). Compared with the controls,the model rats showed remarkably increased mRNA and protein expressions of NR2 B in the dorsal root ganglion( P < 0. 05) but not in the spinal dorsal horn at 4 hours. However,no statistically significant difference was found in the expression of NR1 either in the dorsal root ganglion or in the spinal dorsal horn between the two groups( P > 0. 05). Conclusion: The NMDA receptor plays an important role in pathogenesis of orchialgia in rats. In the early stage of pain,upregulating the expression of the subunit NR2 B of the NMDA receptor can mediate peripheral hyperalgesia and consequently orchialgia. Natl J Androl,2019,25( 4) : 296-301
引文
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