摘要
目的对完全弗氏佐剂（CFA）慢性炎性疼痛模型不同时间段的脊髓以及背根神经节miRNA-28表达进行荧光定量PCR分析，鞘内注射miRNA-28模拟物并观察大鼠热激疼痛行为学变化，预测miRNA-28下游作用靶标基因。方法采用CFA制备慢性炎性疼痛SD大鼠模型；从大鼠脊髓和背根神经节组织中提取miRNA，运用RT—qPCR方法对miRNA-28进行定量分析；鞘内微注射miRNA-28模拟物，热激法检测大鼠疼痛行为；使用3种不同的生物信息学预测软件对miRNA-28靶标进行分析；Western—blot方法检测CFA模型大鼠第3天时背根神经节中Nnat蛋白表达。结果miRNA-28在CFA疼痛模型脊髓和背根神经节中均有表达，但表达情况并不-致：miRNA-28在背根神经节表达差异明显，其中以第3天最为显著，下调至对照水平的1．28％；在脊髓组织，2h时miRNA-28已经下调至对照水平的55．56％，第3天时又上调至对照水平的190％，第7天又下调至对照水平的83％。鞘内微注射miRNA-28模拟物后明显减轻CFA大鼠疼痛反应。生物信息学分析表明Nnat可能是miRNA-28作用的靶标基因。CFA模型大鼠第3天时背根神经节中Nnat蛋白明显升高。结论miRNA-28可能在背根神经节水平通过调控Nnat参与慢性炎性疼痛的发生、维持和调控。
Objective To analyze miRNA-28 expression in spinal cord and dorsal root ganglion in SD rats with complete Freund＇s adjuvant （CFA）-induced chronic inflammatory pain in different time segment by iluorescence quanti-tative PCR, to observe thermal hyperalgesia behavior change of rats by intrathecal injection of miRNA-28 analogue, and to predict downstream target gene of miRNA - 28. Methods CFA - induced chronic inflammatory pain model in rats was established, miRNA from spinal cord and dorsal root ganglion tissue in rats was extracted and qRT - PCR method was used for quantitative analysis of miRNA - 28. miRNA - 28 analogue was microinjected intraehecally. Thermal stimulation of paws was used to detect pain behavior in rats. 3 different kinds of biological information prediction software were used to analyze the miRNA-28 targets. Western blot was used to detect the Nnat protein levels in dorsal root ganglion. Re- suits miRNA - 28 was expressed in spinal cord and dorsal root ganglion in CFA - induced pain model rats, but the ex-pression levels of miRNA - 28 were different in different tissues and at different time. The expression of miRNA - 28 in dorsal root ganglion was the lowest on the 3rd day, down to 1.28% of the expression level in control group. In the spinal cord, the expression of miRNA -28 was down to 55.56% of the expression level in control group at 2 h, up to 190% of the expression level in control group on the 3rd day, and down to 83% of the expression level in control group on the 7th day. Intrathecal microinjection of miRNA - 28 analogue significantly reduced pain reaction in CFA - induced pain model rats. Bioinformatics analysis showed that Nnat might be a target gene of miRNA -28. Nnat protein was significantly increased in dorsal root ganglion of the CFA - induced pain model rats within 3 days. Conclusion miRNA - 28 may be involved in the development, persistence, and regulation of chronic inflammatory pain by regulating Nnat in dorsal root ganglion.
出处
《徐州医学院学报》
CAS
2013年第4期214-218,共5页
Acta Academiae Medicinae Xuzhou
基金
国家自然科学基金（81202320）
江苏省自然科学基金（BK2012147）
徐州医学院院长专项人才基金（2012KJZ17）
