内质网应激特有的caspase-12在神经病理性疼痛大鼠脊髓背角的表达

Expression of endoplastic reticulum stress-associated specific caspase-12 in the spinal dorsal horn neuron of neuropathic pain rats

目的:检测内质网应激特有caspase-12凋亡途径与神经病理性疼痛模型大鼠脊髓背角神经元凋亡之间的关系.方法:SD雄性大鼠随机分为假手术组(sham)和坐骨神经慢性压迫(CCI)模型组.检测大鼠在手术前及术后21 d的热痛敏和机械痛敏;CCI术后21d,免疫组织化学检测大鼠脊髓背角内葡萄糖调节蛋白78(GRP78)、caspase-12和caspase-3的表达;TUNEL法检测脊髓背角内细胞的凋亡.结果:与假手术组相比,模型组的热痛敏和机械痛敏在术后均明显下降,脊髓背角内GRP78、caspase-12和caspase-3的表达均增高,凋亡染色阳性细胞数目也较多.结论:坐骨神经慢性压迫模型大鼠脊髓背角内神经元凋亡的途径之一是内质网应激特有caspase-12介导的,可能与神经病理性疼痛的发生、发展有关.

Objective:To investigate whether apoptosis of the spinal dorsal horn neuron in neuropathic pain rats caused by chronic constriction injury(CCI) of the sciatic nerve is induced by endoplastic reticulum stress(ERS)-associated specific caspase-12-dependent pathway.Methods:SD rats were divided into two groups:a sham group and CCI group randomly.Paw withdraw thresholds(PWTs) and the paw withdrawal thermal latency(PWTL) were examined.The expression of GRP78(a marker protein of endoplastic reticulum stress),caspase-12 and caspase-3 was measured with immunohistochemistry,and apoptosis was tested by TUNEL method in the spinal dorsal horn in two group on day 21.Results:Compared with the sham group,the PWTs and PWTL decreased significantly after operation;GRP78,caspase-12,caspase-3 expression and the number of apoptotic cells in spinal dorsal horn neurons increased significantly 21 days after operation in the CCI group.Conclusion:The ERS associated specific caspase-12-dependent pathway may be one of the pathways related to the spinal dorsal horn neuron apoptosis in neuropathic pain rats caused by chronic constriction injury.