鞘内注射丹参酮ⅡA对坐骨神经慢性压迫性痛大鼠脊髓背角内磷酸化p38MAPK的影响

Effects of intrathecal injection of tanshinone IIA on expression of phosphorylated p38 mitogen-activated protein kinase in spinal dorsal horn of neuropathic pain rats

目的：研究丹参酮ⅡA （TSA）对坐骨神经慢性压迫性痛大鼠脊髓背角内磷酸化p38丝裂原活化蛋白激酶（p-p38MAPK）表达的影响,探讨丹参酮ⅡA的镇痛机制.方法：SD雄性大鼠随机分为假手术组（sham组）和模型组.模型组又分为生理盐水组（NS组）和处理组（TSA组）.模型组在手术当日及术后每日鞘内注射生理盐水0.1ml和丹参酮ⅡA20 mg/kg,连续注射10d.检测各组大鼠在手术前及术后10d的机械痛阈和热痛阈;术后第10天,免疫组织化学和免疫蛋白印迹检测大鼠脊髓背角内p-p38MAPK的表达.结果：与假手术组比较,生理盐水组大鼠的机械痛阈和热痛阈明显降低,p-p38MAPK的表达增多;与生理盐水组比较,处理组的机械痛阈和热痛阈明显升高,脊髓背角内p-p38MAPK的表达下降,差异均有统计学意义.结论：鞘内注射丹参酮ⅡA对坐骨神经慢性压迫性痛模型大鼠的镇痛作用可能与降低脊髓背角内p-p38MAPK的表达有关.

Objective To observe effects of intrathecal injection of tanshinone HA on exPression of Phosphorylated p 38mitogen-activated Protein kinase （ p_p 3 8MAPK） in sPinal dorsal horn of neuro Pathic Pain mechanism of tanshinone HA Methods： Adult SD rats were randomly divided into two groups： sham group and chronic constriction injury of the sciatic nerve （CCI） group. CCI group was randomly and evenly divided into two groups： saline group and treatment group （TSA group）. Nature saline 0. 1 ml and tanshinone HA 20 mg/kg were intrathecally injected respectivelyfrom the day of operation to 10 d after operation daily in the CCI group. Before and after operation,mechanical nociceptive thresholds were assessed by paw withdrawal thresholds （PWTs） with von Frey filament and the paw withdrawal thermal latency （PWTL） was examinated. p-p38MAPK was measured with immunohistochemical staining method and Westernblotting in the spinal dorsal horn of groups on 10 d after operation. Results： Compared with the sham group,the PW Ts andPWTL decreased,and the expression of p-p38MAPK increased significantly in the saline group in the spinal dorsal horn 10days after operation. Compared with the saline group,the PWTs and PWTL increased,and the expression of p-p38MAPKdecreased significantly in the TSA group in the spinal dorsal horn 10 days after operation. Conclusiotanshinone HA can exert analgesic effect on neuropathic pain rats by decreasing the dorsal horn.