Cx43及GLT-1对三叉神经痛大鼠疼痛行为学变化的调控作用

REGULATION OF Cx43 AND GLT-1 ON PAIN BEHAVIOR IN RATS WITH TRIGEMINAL NEURALGIA

目的:研究大鼠三叉神经痛模型中缝隙连接蛋白43(connexin-43,Cx43)和谷氨酸转运体-1(glutamate transporter-1,GLT-1)表达的变化,探讨Cx43和GLT-1与三叉神经痛大鼠疼痛行为的关系。方法:将42只SD大鼠随机分为正常组(N)、假手术组(S)、模型组(ION-CCI)、ION-CCI+生理盐水1组(NS1)、ION-CCI+Gap26组(Gap26)、ION-CCI+生理盐水2组(NS2)、ION-CCI+头孢曲松组(Cef),每组6只。用铬肠线疏松结扎大鼠眶下神经建立三叉神经痛动物模型;造模成功后,相应组于术后第8天分别腹腔注射Gap26、头孢曲松或生理盐水;假手术组仅暴露神经,不结扎。于术前1天,术后1、3、5、7、9、11、14天行机械痛阈值及视频行为学检测。术后第15天取三叉神经脊束核,应用蛋白质印迹检测Cx43和GLT-1蛋白表达水平。结果:腹腔注射Gap26或头孢曲松可提高三叉神经痛大鼠的机械痛阈值(P<0.001),减少其抓脸次数(P<0.001)。术后第15天,ION-CCI、NS1及NS2组大鼠较N组及S组大鼠相比,Cx43表达明显增加(P<0.01),GLT-1表达明显减少(P<0.001);Gap26组大鼠较ION-CCI、NS1组大鼠相比,Cx43表达减少(P<0.05),GLT-1表达增加(P<0.01);Cef组大鼠较ION-CCI、NS2组大鼠相比,GLT-1表达增加(P<0.001),Cx43表达无明显差异。结论:腹腔注射Gap26或头孢曲松可改变三叉神经痛大鼠疼痛行为并改变三叉神经脊束核中Cx43和GLT-1的表达,提示Cx43和GLT-1参与了三叉神经痛大鼠疼痛行为的变化。

Objective： To investigate the expression of connexin-43 （Cx43） and glutamate transporter-1 （GLT-1）, and the relationship among Cx43, GLT-1 and the pain behaviors of trigeminal neuralgia model of rats. Methods： Forty-two Sprague-Dawley rats were randomly divided into Normal （N）, Sham （S）, Model （ION-CCI）, ION-CCI ＋ normal saline 1 （NS1）, ION-CCI ＋ Gap26 （Gap26）, ION-CCI ＋ normal saline 2 （NS2）, and ION-CCI ＋ ceftriaxone groups （Cef）, with 6 rats in each group. Rat model of the trigeminal neuralgia was established by ligating the inferior orbital nerve with a chromium enteric line. Inferior orbital nerve was only exposed without ligation in S group. Gap26, cefiriaxone or normal saline was intraperitoneally injected into different groups at the 8th day after surgery. The mechanical pain threshold and video behavior were detected at 1 day before surgery and 1, 3, 5, 7, 9, 11, 14 days after surgery. The spinal trigeminal nucleus was dissected on postoperative day 15. The expression levels of Cx43 and GLT-1 protein were detected by Western Blot. Results： Intraperitoneal injection of Gap26 or ceftriaxione increased mechanical pain threshold （P 〈 0.001） and reduced the time of face-grooming （P 〈 0.001） in ION-CCI rats.On the 15thday after surgery, compared with N and S group, the expression of Cx43 or GLT-1 were significantly increased （P 〈 0.01） or reduced （P 〈 0.001） separately in ION-CCI, NS1 and NS2 groups. Compared with ION-CCI and NS1 group, the expression of Cx43 in Gap26 group was decreased （P 〈 0.05）, and the expression of GLT-1 was increased （P 〈 0.01）. Compared with ION-CCI and NS2 group, the expression of GLT- 1 in Cef group was increased （P 〈 0.001）, and there was no significant difference in Cx43 expression. Conclusion： Intraperitoneal injection of Gap26 or ceRriaxone can change the pain behavior in ION-CCI rats and change the expression of Cx43 and GLT-1 in the spinal trigeminal nucleus, suggesting that Cx43 and GLT-1 were involved in the changes of pain behavior of the trigeminal neuralgia in rats.