曲马多对CCI大鼠DRG细胞SP、CGRP表达及胃液PH值和胃粘膜的影响

EFFECTS OF TRAMADOL ON SP AND CGRP EXPRESSIONS OF DRG NEURONS AND ON PH VALUE OF GASTRIC JUICE AND THE STRUCTURE OF GASTRIC MUCOSA IN CCI RATS

目的：观察曲马多对坐骨神经结扎（CCI）大鼠机械痛敏、背根神经节（DRG）SP和CGRP表达、胃液pH和胃窦粘膜的影响。方法：22只雄性SD大鼠，建立右侧CCI模型，分为生理盐水组（NS组，11=6）、曲马多1mg／kg组（T1组，n=8）和曲马多4mg／kg组（他组，n=8）。自术后第8天分别给予生理盐水、曲马多1mg／kg和4mg／kg灌胃，每日两次共7天。观察大鼠后肢机械痛阈，M～5DRGSP和CGRP表达，胃液pH值和胃窦粘膜变化。结果：（1）灌胃第3天和第7天，T1组和他组右后肢痛阈与NS组相比显著增加（P〈0．05）；（2）灌胃第7天，右侧DRGSP和CGRP表达与Ns组相比显著降低（P〈0．05）；（3）灌胃后第3天和第7天，T1组和T2组胃液pH值显著升高（P〈0．05），且胃窦粘膜未见异常。结论：曲马多降低CCI大鼠机械痛敏，减少DRGSP和CGRP表达，提高胃液pH值，对胃窦粘膜无影响。

Objective： To obseve the effects of tramadol on mechanical hyperalgesia, SP and CGRP expression of dorsal root ganglion （DRG） neurons, and on pH value of gastric juice as well as the structure of gastric mucosa in CCI rats. Methods： 22 male SD rats were randomly divided into normal saline group （ NS group） （ n = 6）, tramadol 1 mg/kg group （ T1 group） （ n = 8 ） and tramadol 4 mg/kg group （ T2 group） （n = 8）. From the 8th day of post-ligation, NS, tramadol 1 mg/kg and tramadol 4 mg/kg were injected into gastric cavity twice per day for 7 days, respectively. Before and after treatment, the posteri- or paw withdrawal mechanical threshold （PWMT） was measured, and the expressions of SP and CGRP in IA-5 DRG neurons were detected. In addition, PH value of gastric juice and the structure of gastric mucosa were observed. Results： （1） On 3rd and 7th day, the right PWMTs in T1 and T2 groups were sig- nificantly increased compared with that in NS group （P 〈0.05） ; （2） On 7th day, the SP and CGRP expressions of the right DRG were significantly reduced in T1 and T2 group compared with NS group （P 〈 0.05 ） ; （3） On 3rd and 7th day, the pH values were significantly increased in T1 and T2 groups （P 〈 0.05）. On 7th day, there was no obvious abnormality in the structure of gastric mucosa. Conclusion ： Tramadol decreased the mechanical hyperalgesia, reduced SP and CGRP expressions in DRG neurons, and increased the PH value of gastric juice without obvious gastric mucosal injuries in CCI rats.