鞘内注射曲马多对手术致痛大鼠脊髓c-fos蛋白表达的影响

Effect of intrathecal injection of tramadolon the expression of c-fos protein in spinaldorsal horn of incision-induced pain in rats

目的在大鼠手术致痛模型中研究鞘内注射曲马多对脊髓c-fos蛋白的影响,探讨曲马多的超前镇痛效应。方法选取鞘内置管成功的32只雄性大鼠随机分为4组,每组8只,分别为假手术组(S组),实验对照组(EC组),术前曲马多组(TP20组,20μg/10μl)以及术后曲马多组(PT20组,20μg/10μl)。按照Brennan法制成大鼠切口痛模型,致痛2 h后,深麻醉大鼠,灌注固定,取脊髓L4～L6节段做c-fos免疫组化染色,观察大鼠脊髓c-fos蛋白表达的变化情况。结果 3个实验组的IOD值与假手术组相比较,均有不同程度的升高,差异有统计学意义(P<0.05);TP20组、PT20组的IOD值与EC组相比较,均弱于实验对照组,差异有统计学意义(P<0.05);TP20组的IOD值与PT20组相比较,差异有统计学意义(P<0.05)。结论手术致痛前或后,鞘内注射曲马多均能抑制大鼠脊髓背角c-fos蛋白的表达;曲马多预先给药,抗伤害作用更好,具有超前镇痛效应。

Objective To study the effect of intrathecal injection of tramadol on the expression of c-fos protein in the spinal dorsal horn in the incision-induced rats so as to explore the preemptive analgesia effect of tramadol. Methods 32 rats selected the successful control of the built-in sheath were randomly divided into four groups：sham-operated group（S group）, experimental control group （EC group）, preoperative tramadol group （TP20 group, 20μg/10μL）, postoperative tramadol group （PT20 group, 20μg/10μL） . Each group included 8rats. According to the Brennan method, Each group at 2h after incision-induced pain, perfusion fixed, check L4-L6 spinal cord segment to do c-fos immunohistochemistry,observe the changes of expression of c-fos protein in the spinal dorsal horn of rats. Results IOD values of the three experimental groups compared with sham-operated group, have different degrees higher, the difference was statistically significant （P〈0.05）;IOD values of TP20 group and PT20 group compared with the EC group, were significantly lower than experimental control group, the difference was statistically significant （P〈0.05） ;IOD value of TP20 group compared with the PT20 group, the difference was statistically significant （P〈0.05）. Conclusion No matter before or after incision -induced pain,intrathecal injection of tramadol can inhibit the expression of c-fos protein in the spinal dorsal horn of rats;tramadol administration in advance, the better the role of anti-inju- ry, with obvious effect of preemptive analgesia.