脊髓胶质细胞在小鼠骨癌痛形成中的作用

目的 评价脊髓胶质细胞在小鼠骨癌痛形成中的作用.方法 健康雄性C3H/He小鼠40只,周龄8～10周,体重18～22 g,随机分为4组(n=10):假手术组(S组)、骨癌痛组(B组)、PBS组(P组)和米诺环素组(M组).S组跟骨骨髓腔内注射PBS 10 μl;余3组跟骨骨髓腔内注射含2×105个骨纤维肉瘤细胞的PBS 10 μl制备骨癌痛模型,于造模前即刻开始PBS组鞘内注射PBS 5μl,M组鞘内注射米诺环素(用PBS溶解为0.2 mmol/L)5μl,1次/d,连续11 d.于造模前1 d、造模后即刻、3、5、7、9、11 d时测定机械痛阈;于造模后3、7、9、11 d机械痛阈测定结束后测定冷痛阈.痛阈测定结束后处死小鼠,取脊髓组织,测定神经胶质纤维酸性蛋白(GFAP)和CD11b的表达水平.结果 与S组比较,B组和P组造模后3-11 d时、M组造模后3、5 d时机械痛阈升高,B组、P组和M组造模后7～11 d时冷痛阈升高,脊髓CD11b和GFAP表达上调(P<0.05).与B组比较,M组造模后3-11 d时机械痛阈降低,造模后7-11 d时冷痛阈降低,脊髓CD11b和GFAP表达下调(P<0.05).结论 脊髓胶质细胞(星形胶质细胞和小胶质细胞)的激活参与了小鼠骨癌痛的形成.     

神经病理性痛大鼠脊髓背角星形胶质细胞NF-κB活性的变化

目的 观察神经病理性痛大鼠脊髓背角星形胶质细胞NF-κB活性的变化,以探讨脊髓星形胶质细胞调控神经病理性痛时胞内可能的信号转导通路机制.方法 雄性SD大鼠16只,月龄2～3 71,体重220～280 g,随机分为2组(n=8):假手术组(S组)和神经病理性痛组(CCI组).CCI组采用慢性压迫性损伤法制备大鼠慢性神经病理性痛模型,S组仅暴露坐骨神经.分别于术前1 d和术后7 d测定机械痛阈和热痛阈,术后第7天测定痛阈后处死大鼠,取脊髓,记录腰段脊髓背角星形胶质细胞核内NF-κBp65的免疫反应阳性细胞数.结果 与术前1 d比较,CCI组大鼠术后7 d机械痛阈和热痛阈降低(P<0.05).与S组比较,CCI组大鼠术后7 d机械痛阈和热痛阈降低,术侧脊髓背角星形胶质细胞NF-κBp65免疫阳性细胞数增多(P<0.05).结论 脊髓背角星形胶质细胞参与大鼠神经病理性痛的调控,其机制可能与NF-κB信号转导通路有关.     

鞘内注射氟代柠檬酸对神经病理性疼痛大鼠的镇痛作用

目的通过观察鞘内注射星形胶质细胞特异性抑制剂氟代柠檬酸(FC)对神经病理性疼痛大鼠的镇痛作用,探讨脊髓星形胶质细胞在神经病理性疼痛中的作用。方法雄性SD大鼠32只,随机分为4组(n=8),A组行假手术,鞘内注射FC的溶媒;B组行假手术,鞘内注射FC;C组制作坐骨神经慢性压迫性损伤(CCI)模型,鞘内注射FC的溶媒;D组制备CCI模型,鞘内注射FC。鞘内置管后3 d,制备CCI模型,术后1 d开始行鞘内注射,1次/d(容积1μl),连续6 d,剂量为1 nmol/μl。分别于术前1 d(基础值)、术后1、3、5、7 d测定大鼠的机械痛阈和热痛阈。术后7 d测定热痛阈后立即处死大鼠,取L4.5脊髓组织,其中4只用于免疫组化实验(测定IL-6表达),另外4只用于RT-PCR实验(测定IL-6 mRNA表达)。结果CCI可导致机械痛阈和热痛阈降低,脊髓组织IL-6 mRNA和IL-6表达增加;而鞘内注射FC可在一定程度上抑制CCI导致的上述改变。结论脊髓星形胶质细胞的激活参与大鼠神经病理性疼痛的调节。     

神经病理性疼痛大鼠脊髓星形胶质细胞增殖活化的变化

目的观察神经病理性疼痛大鼠脊髓星形胶质细胞增殖活化的变化。方法健康成年雄性SD大鼠48只，随机分为假手术组和手术组（n=24），慢性坐骨神经挤压损伤（CCI）前1d、CCI后1、4、7、14、28d各随机取4只大鼠，测定机械痛阈和热痛阈后立即处死大鼠，取L4，5脊髓，用免疫组化方法观察胶质纤维酸性蛋白（GFAP）表达以反映星形胶质细胞激活情况。结果CCI后1d术侧机械痛阈和热痛阈开始下降，机械痛阈CCI后7d下降至最低，热痛阈CCI后4d下降至最低，CCI后28d仍处于较低水平（P〈0．05或0．01）；手术组术侧脊髓后角GFAP表达于CCI后4d开始增加，至CIC后7d达高峰，至CCI后28d仍维持于高水平（P〈0．05）。结论脊髓星形胶质细胞的增殖活化参与神经病理性疼痛的发生和维持。     

脊髓背角星形胶质细胞NF-κB在紫杉醇诱发大鼠神经病理性痛中的作用

目的 评价脊髓背角星形胶质细胞NF-κB紫杉醇诱发大鼠神经病理性痛中的作用.方法 健康雄性SD大鼠20只,6周龄,体重180～200 g,采用随机数字表法,将其随机分为2组(n＝10):对照组(C组)和神经病理性痛组(NP组).NP组隔日腹腔注射紫杉醇2 mg/kg,共4次;对照组隔日腹腔注射生理盐水1 ml/kg,共4次.于给药前和给药结束后1、7、14 d时分别测定体重、机械痛阈和热痛阈.给药结束后14 d时,处死大鼠,取L4～6脊髓组织,采用免疫荧光法测定脊髓背角星形胶质细胞NF-κB p65的表达.结果 两组体重比较差异无统计学意义(P＞0.05).与C组比较,NP组给药结束后7和14 d时机械痛阈和热痛阈降低,脊髓背角星形胶质细胞NF-κB p65表达上调(P＜0.05或0.01).结论 紫杉醇通过激活脊髓星形胶质细胞中的NF-κB,诱发大鼠神经病理性痛.     

骨癌痛大鼠脊髓NF-κB、IL-6和TNF-α表达的变化

目的 评价骨癌痛大鼠脊髓NF-κB、IL-6和TNF-α表达的变化.方法 雌性健康SD大鼠72只,体重150～180 g,随机分为3组(n=24):对照组(C组)、假手术组(S组)和骨癌痛组(BP组).BP组于大鼠左侧胫骨干骺端骨髓腔内注射5μl Walker 256(1×105)乳腺癌细胞制备骨癌痛模型,S组左胫骨上端注射Hank液5μl.分别于肿瘤细胞接种前、接种后2、4、6、9、12、14、16、18和21 d时测定机械阈值.分别于肿瘤细胞接种后6、12和18 d时,处死3只大鼠,取L4-6脊髓组织,采用RT-PCR法测定NF-κB p65 mRNA、IL-6 mRNA和TNF-α mRNA的表达;另处死3只大鼠,取L4-6脊髓组织,计数NF-κBp65阳性细胞,采用免疫组化法测定NF-κB p65表达.结果 与C组和S组比较,BP组机械痛阈降低,脊髓NF-κB p65及其mRNA、IL-6 mRNA和TNF-αmRNA的表达上调,NF-κB p65阳性细胞计数增加(P＜0.05或0.01);C组和S组间上述指标比较差异无统计学意义(P＞0.05).结论 大鼠胫骨骨髓腔内注射肿瘤细胞通过激活脊髓NF-κB,导致炎性细胞因子IL-6和TNF-α大量释放,从而诱发骨癌痛.     

重组人促红细胞生成素对L5脊神经切断大鼠痛阈及脊髓TNF-α和IL-1β表达的影响

目的 观察重组人促红细胞生成素(rhEPO)对L5脊神经切断大鼠机械和热痛阈及脊髓TNF-α和IL-1β表达的影响.方法 SD雄性大鼠50只随机分为五组:脊神经损伤rhEPO1 000、3 000、5 000 U/kg组(R1、R2、R3组)和生理盐水组(N组)及假手术组(C组),每组10只.术前1 d给药,连续7 d.测定术前当天及术后3、7、14 d大鼠的机械性缩足反射阈值(MWT)和热缩足潜伏期(TWL)及术后14 d各组大鼠L5脊髓肿瘤坏死因子α(TNF-α)、白细胞介素1β(IL-1β)的水平.结果 L5脊神经损伤术后大鼠术侧MWT降低、TWL缩短、脊髓TNF-α和IL-1β的表达增高(P<0.01).与N组比较,R1组术后各时间点的MWT和TWL无明显改变;R2和R3组MWT增高、TWL延长(P<0.05);脊髓TNF-α、IL-1β水平降低(P<0.01).结论 腹腔注射rhEPO 3 000或5 000U/kg能缓解L5脊神经切断大鼠的机械和热痛敏,抑制脊髓TNF-α和IL-1β的表达.     

脊髓趋化因子配体2在大鼠胫骨癌痛中的作用

目的 探讨脊髓趋化因子配体2(CCL2)在大鼠骨癌痛中的作用.方法 健康成年雌性SD大鼠84只,体重160～ 180g,采用随机数字表法,将其随机分为3组(n=28):正常对照组(C组)、假手术组(S组)和骨癌痛组(P组).P组胫骨骨髓腔内注射Walker-256乳腺癌细胞混悬液制备大鼠胫骨癌痛模型;S组胫骨骨髓腔内注射生理盐水;C组不作任何处理.于接种前ld、接种后l、3、7、10、14和21 d时,测定机械性刺激阈值.于接种前ld、接种后7、14和21'd时痛阈测定结束后,各组随机处死6只大鼠,取L4～6脊髓组织,采用ELISA法测定CCL2含量,反映其表达.接种后14 d时痛阈测定结束后,P组随机取4只大鼠,采用免疫荧光双标染色法观察脊髓背角CCL2与离子钙接头蛋白分子-1(小胶质细胞特异性标记物)、胶质纤维酸性蛋白(星形胶质细胞特异性标记物)和神经元特异核蛋白(神经元特异性标记物)的共表达情况.结果 与C组和S组相比,P组接种后7～21 d时机械性刺激痛阚下降,接种后7、14和21 d时脊髓CCL2表达上调(P＜0.05).骨癌痛大鼠脊髓背角CCL2在小胶质细胞和星形胶质细胞中存在表达,而在神经元中无表达.结论 脊髓小胶质细胞和星形胶质细胞中释放的CCL2参与了大鼠胫骨癌痛的发生发展.     

沉默髓系细胞触发受体1基因对神经病理性痛大鼠的影响

目的探讨髓系细胞触发受体1(triggering receptor expressed on myeloid cells 1,TREM1)在大鼠神经病理性痛中的作用及可能机制。方法成年雄性SD大鼠,体重220~300 g,取鞘内置管成功大鼠48只,随机分为四组(n=12):对照组(S组)、神经病理性痛组(CCI组)、TREM1sh RNA组(RNAi组)和阴性慢病毒组(Virus组)。采用慢性坐骨神经压榨性损伤法(CCI)制备神经病理性痛模型。RNAi组于造模前1周鞘内注射p GLVU6/RFP/Puro-sh RNA 30μl(1×109IU/ml);Virus组、CCI组和S组分别鞘内注射等量阴性慢病毒和生理盐水。于造模前1 d和造模后1、3、7、14d测定机械缩足反应阈(MWT)和热缩足潜伏期(TWL)。于造模后14 d痛阈测定结束后,处死大鼠,取L4-5节段脊髓组织,采用Western blot法测定脊髓TREM1、TLR4、My D88、IκBα和p-NF-κB p65蛋白含量,RT-PCR法测定脊髓IL-1β、TNF-α和IL-6 mRNA表达量。结果与S组比较,CCI组和Virus组TREM1蛋白含量明显增加(P0.05);与CCI组比较,RNAi组TREM1蛋白含量明显降低(P0.05)。与S组比较,CCI组、RNAi组和Virus组造模后各时点MWT和TWL明显降低(P0.05);脊髓TLR4、My D88和p-NF-κB p65蛋白含量明显增加,IκBα蛋白含量明显降低(P0.05);IL-1β、TNF-α和IL-6 mRNA表达量明显升高(P0.05)。与CCI组比较,RNAi组大鼠造模后各时点MWT和TWL明显升高(P0.05);脊髓TLR4、My D88和p-NF-κB p65蛋白含量明显降低,IκBα蛋白含量明显增加(P0.05);IL-1β、TNF-α和IL-6 mRNA表达量明显降低(P0.05)。结论干扰TREM1基因可以缓解大鼠神经病理性痛,其机制可能与抑制TLR4/My D88/NF-κB通路有关。     

脊髓TNF-α在小鼠骨癌痛发生中的作用

目的 探讨脊髓TNF-α在小鼠骨癌痛发生中的作用.方法 雄性C3H/He小鼠72只,体重18～25 g,周龄4～6周,随机分为3组(n=24):假手术组(S组)、骨癌痛组(BCP组)和TNF-α拮抗剂依那西普组(E组).采用股骨远端骨髓腔注射肿瘤细胞的方法制备小鼠骨癌痛模型,S组注射等量不含肿瘤细胞的α-MEM,E组于注射肿瘤细胞前3 d、注射前即刻、注射后3、6 d时分别腹腔注射依那西普100μg(溶于0.5 ml生理盐水).分别于注射肿瘤细胞前、注射后3、5、7、10、14 d(T1～6)时测定热痛阈和机械痛阈.分别于T4～6时随机取8只小鼠测定痛阈后处死取脊髓,采用RT-PCR法检测TNF-αmRNA的表达水平.结果 与S组比较,BCP组T3～6时热痛阈和T5、6时机械痛阈降低,T4～6时TNF-αmRNA表达上调,E组T4～6时热痛阈降低,T5,6时机械痛阈降低、TNF-αmRNA表达上调(P<0.05);与BCP组比较,E组T4～6时热痛阈、T6时机械痛阚升高,T5,6时TNF-α mRNA表达下调(P<0.05).结论 脊髓TNF-α参与了小鼠骨癌痛的发生.     

胫骨癌痛大鼠脊髓Toll样受体4及其下游细胞因子表达的变化

目的 评价胫骨癌痛大鼠脊髓Toll样受体4(TLR4)及其下游细胞因子(TNF-α和IL-1β)表达的变化,探讨TLB4信号转导通路在骨癌痛中的作用.方法 健康雌性SD大鼠72只,体重150～180 g,随机分为3组(n=24):正常对照组(C组)、假手术组(S组)和胫骨癌痛组(BP组).BP组于大鼠左侧胫骨干骺端骨髓腔内注射5μl Walker 256(1×10~5)乳腺癌细胞制备胫骨癌痛模型,S组仅左侧胫骨上端注入Hank液5μl.于接种前(基础状态)、接种后2、4、6、9、12、14、16、18和21 d时行痛行为学评分,测定机械痛阈.于接种后6、12、18 d时行胫骨X线摄片,观察胫骨破坏情况,并于各时点取3只大鼠,处死后取L_(4～6)脊髓,测定TLR4、TNF-α和IL-1β的mRNA表达,各时点另取3只大鼠,处死后取L_(4～6)脊髓,计数TLR4阳性细胞;测定TLR4蛋白表达.结果 与基础值比较,BP组接种后6～21 d时痛行为学评分逐渐升高,机械痛阈逐渐降低(P＜0.05),C组和S组各时点痛行为学评分差异无统计学意义(P＞0.05).与C组和S组比较,BP组痛行为学评分升高,机械痛阈降低,TLR4 mRNA和蛋白、TNF-α mRNA和IL-1β mRNA表达上调,TLR4 阳性细胞计数增多(P＜0.05或0.01).BP组接种后6 d即可见左侧胫骨上端骨小梁轻微缺损,12 d时多处骨小梁缺损,骨皮质破坏,18 d时胫骨上端双侧骨皮质明显破坏,大片骨质缺损.结论 大鼠胫骨骨髓腔内肿瘤细胞通过激活脊髓TLR4,导致其下游细胞因子大量释放,而诱发骨癌痛.TLR4可能是胫骨癌痛潜在治疗靶点.     

μ受体在抗神经生长因子抗体减轻大鼠骨癌痛中的作用

目的 评价μ受体在抗神经生长因子抗体(anti-NGF)减轻大鼠骨癌痛中的作用.方法 实验一健康雌性SD大鼠60只,体重200～220 g,随机分为4组(n=15):假手术组(S组)、假手术+anti-NGF组(SN组)、骨癌痛组(P组)和骨癌痛+anti-NGF组(PN组).P组和PN组于左侧胫骨上段骨髓腔内注射10μl Walker256乳腺癌细胞(1×105个)制备骨癌痛模型;S组和SN组于左侧胫骨上段注射PBS 10μl.于肿瘤细胞接种后13 d时,进行鞘内置管.鞘内置管成功后3 d,SN组和PN组鞘内注射anti-NGF 10μg(用生理盐水稀释至10μl),S组和P组鞘内注射生理盐水10μl,2次/d,连续5 d.于肿瘤细胞接种前、肿瘤细胞接种后13、16、18、21 d时测定自发缩足次数(NSF)、热缩足潜伏期(PWL)和机械性痛阈(PWT).肿瘤细胞接种后21 d时,处死大鼠,取L4.5段脊髓背角和背根神经节,测定μ受体及其mRNA的表达.实验二健康雌性SD大鼠30只,体重200～220 g,随机分为2组(n=15):骨癌痛+anti-NGF组(PN组)和骨癌痛+纳洛酮+anti-NGF组(PNN组).于左侧胫骨上段骨髓腔内注射10μlWalker256乳腺癌细胞(1×105个)制备骨癌痛模型.于肿瘤细胞接种后13 d时,进行鞘内置管.鞘内置管成功后3 d,PN组鞘内注射鞘内注入anti-NGF 10μg(生理盐水稀释至25μl);PNN组鞘内注射纳洛酮10μg(生理盐水稀释至25μl),0.5 h后,鞘内注射anti-NGF 10μg(生理盐水稀释至25 μl),2次/d,连续5 d.于肿瘤细胞接种前、肿瘤细胞接种后13、16、18、21 d时测定大鼠NSF、PWL和PWT.结果 实验一与S组比较,SN组NSF、PWL和PWT差异无统计学意义,SN组和PN组μ受体及其mRNA表达差异无统计学意义(P＞0.05),P组和PN组瘤细胞接种后13～21 d时NSF增加,PWL缩短,PWT降低,P组μ受体及其mRNA表达下调(P＜0.05或0.01);与P组比较,PN组肿瘤细胞接种后18～21 d时NSF减少,PWL延长,PWT升高,μ受体及其mRNA表达上调(P＜0.05或0.01).实验二与PN组比较,PNN组肿瘤细胞接种后18～21 d时NSF增加,PWL缩短,PWT降低(P＜0.05或0.01).结论 anti-NGF减轻大鼠骨癌痛与μ受体的激活有关.     

鞘内注射氯胺酮对神经病理性痛大鼠吗啡耐受时脊髓背角突触重塑的影响

目的 探讨鞘内注射氯胺酮对神经病理性痛大鼠吗啡耐受时脊髓背角突触重塑的影响.方法 鞘内置管成功的雄性SD大鼠48只,体重200～250 g,采用随机数字表法,将大鼠随机分为6组(n=8),置管后5 d,神经病理性痛组(NP组)、生理盐水对照组(NS组)、吗啡组(M组)、氯胺酮组(K组)和吗啡+氯胺酮组(MK组)采用背根神经节慢性压迫法制备神经病理性痛模型,假手术组(S组)仅暴露L5椎间孔.背根神经节慢性压迫后1 d NS组鞘内注射0.9%生理盐水20止,M组和K组分别给予吗啡20μg或氯胺酮50μg,MK组给予吗啡20μg+氯胺酮50μg,1次/d,连续14 d.分别于给药前(基础状态)、给药1、3、5、7、9、11、14 d时测定机械缩足阈值(PWT)和热缩足潜伏期(PWL).最后1d给药后立即处死大鼠,取脊髓组织,其中4只采用免疫组织化学方法测定脊髓背角突触数目,另外4只用于测定脊髓背角突触后膜致密物厚度.结果 与S组比较,其余5组PWT降低,PWL缩短,NP组、NS组、M组和K组突触数目和突触后膜致密物厚度增加(P＜0.05);与NP组比较,M组、K组和MK组PWT升高,PWL延长,突触数目和突触后膜致密物厚度降低(P＜0.05);与M组比较,MK组PWT升高,PWL延长,突触数目和突触后膜致密物厚度降低(P＜0.05).结论 鞘内注射氯胺酮可抑制神经病理性痛大鼠吗啡耐受时脊髓背角突触重塑.

Abstract：

Objective To investigate the effects of intrathecal (IT) ketamine on the synapsis remodeling in the spinal dorsal horn during devolopment of morphine tolerance in a rat model of neuropathic pain (NP). Methods Male SD rats weighing 200-250 g were used in this study. IT catheter was placed in the subarachnoid space according to Yaksh. Forty-eight SD rats in which IT catheter was successfully placed were randomly divided into 6groups (n=8 each): group sham operation (group S); group NP; group normal saline 20 μl IT(group NS);group morphine 20 μg IT (group M); group ketamine 50 μg IT (group K) and group morphine 20 μ g + ketamine 50 μg IT (group MK). NP was induced by compression of right L4,5 dorsal root ganglions with steel wire inserted through L4,5 intervertebral foramen in NP,M,K and MK groups. Normal saline or morphine and/or ketamine were injected IT once a day for consecutive 14 days. Paw withdrawal threshold (PWT) to mechanical stimulation and paw withdrawal latency (PWL) to a thermal nociceptive stimulus were measured on 0, 1, 3, 5, 7, 9, 11, 14 days during the consecutive 14 days of administration. The animals were sacrificed after the final IT administration. The lumbar segment of the spinal cord was removed for determination of the number of synapsis in the spinal dorsal horn by immuno-histochemistry in 4 animals in each group and observation of synaptic structure remodeling using electron microscope in another 4 animals in each group. Results Compared with group S, PWT was significantly decreased and PWL was shortened in the other 5 groups, and the number of synapsis was significantly increased and the synaptic structure was thickened in NP, NS, M and K groups (P ＜ 0.05). Compared with group NP,PWT was significantly increased and PWL was prolonged in M, K and MK groups, and the number of synapsis was significantly decreased and the thickness of synaptic structure was significantly reduced in group MK ( P ＜ 0.05).Compared with group M, PWT was significantly increased, PWL was prolonged, the number of synapsis was significantly decreased and the thickness of synaptic structure was significantly reduced in group MK ( P ＜ 0.05). Conclusion IT ketamine can inhibit the synaptic remodeling in the spinal dorsal horn during development of morphine tolerance in a rat model of NP.     

慢性吗啡耐受大鼠脊髓背角神经元磷酸化突触素Ⅰ表达的变化

目的 观察慢性吗啡耐受大鼠脊髓背角神经元磷酸化突触素Ⅰ(p-Synapsin Ⅰ)表达的变化.方法 雄性SD大鼠45只,体重150～180 g,月龄1～2月,随机分为5组(n=9):假手术组(S组)、生理盐水组(NS组)、吗啡组(M组)、氯胺酮组(K组)和吗啡+氯胺酮组(M+K组).除S组外,所有大鼠均行鞘内置管,恢复3 d后鞘内给药,NS组给予生理盐水40 μl,M组给予吗啡20 μg,K组给予氯胺酮30μg,M+K组分别给予吗啡20μg及氯胺酮30 μg,2次/d,连续7 d.于给药前(T_0,基础状态)、给药后1、3、5、7 d及停药后1d(T_(1～5))时测定机械缩爪阈值(PWT)与热缩爪潜伏期(PWL),最后一次测定痛阈后处死大鼠,取L3～6脊髓背角,测定p-Synapsin Ⅰ(Ser603)的表达.结果 与基础值比较,M组T_(1,2)时PWT升高,T_(4,5)时PWT降低,T1～3时PWL延长,T_5时PWL缩短,M+K组T_(1～5),时PWT升高,PWL延长(P＜0.05).与S组和NS组比较,M组T_(1,2)时PWT升高,T_(4,5)时PWT降低,T1～3时PWL延长,T_5时PWL缩短,M+K组T_(1～5),时PWT升高,PWL延长(P＜0.05),K组PWT和PWL差异无统计学意义(P＞0.05).与M组比较,M+K组T_(2～5)时PWT升高,T_(3～5)时PWL延长(P＜0.05).与S组和NS组比较,M组和M+K组p-Synapsin Ⅰ(Ser603)表达上调(P＜0.05),K组p-Synapsin Ⅰ(Ser603)表达差异无统计学意义(P＞0.05);与M组比较,M+K组p-Synapsin Ⅰ(Ser603)表达下调(P＜0.05).结论 脊髓背角神经元Synapsin Ⅰ的磷酸化参与了大鼠慢性吗啡耐受的形成,吗啡促进Synapsin Ⅰ磷酸化的部分机制与激活N-甲基-D-天冬氨酸受体有关.     

米诺环素对骨癌痛-吗啡耐受大鼠脊髓CX3C趋化因子受体1mRNA表达的影响

目的 探讨米诺环素对骨癌痛-吗啡耐受大鼠脊髓CX3C趋化因子受体1(CX3CR1)mRNA表达的影响.方法 清洁级雌性SD大鼠,体重180～200 g,月龄3月,经L3,4间隙行鞘内置管,取鞘内置管成功的大鼠60只,采用随机数字表法,将大鼠随机分为4组:正常对照组(C组,n=10)、米诺环素对照组(M组,n=10)、骨癌痛-吗啡耐受组(BM组,n=20)和米诺环素治疗组(BM+M组,n=20).C组不作任何处理;BM组和BM+M组右侧胫骨上段骨髓腔注入Walker256细胞10 μl(400个/μl)制备骨癌痛模型,术后第10天开始鞘内注射吗啡20 μg/kg(100 μl),2次/d,连续7 d,制备骨癌痛-吗啡耐受模型,注射吗啡第8天分别经鞘内注射20μl生理盐水或米诺环素0.25 mg/kg(20 μl),1次/d,连续3 d;M组不行手术,于BM组注射吗啡第8天时鞘内注射米诺环素0.25 mg/kg,1次/d,连续3 d.于术前、术后3、6、9 d、鞘内注射吗啡4、7、10、12 d(T0～7)时测定机械缩足阈值(MWT)和机械缩足持续时间(MWD).C组和M组于T7时,BM组和BM+M组于T6,7时取L4～6脊髓节段,采用免疫组化法检测小胶质细胞标记物——OX-42表达,采用实时PCR法检测CX3CR1 mRNA表达水平.结果 与C组和M组比较,BM组T2,3.5～7时、BM+M组T2,3,5,时MWT降低,MWD延长,CX3CR1 mRNA和OX-42表达上调(P＜0.01).与BM组比较,BM+M组L6,7时MWT升高,MWD缩短,CX3CR1 mRNA和OX-42表达下调(P＜0.01).C组和M组上述指标差异无统计学意义(P＞0.05).结论 米诺环素可抑制骨癌痛-吗啡耐受大鼠脊髓CX3CR1 mRNA的表达,可能是其拮抗吗啡耐受的机制之一.

Abstract：

Objective To investigate the effect of minocycline on spinal CX3 C chemokine receptor 1(CX3 CR1)mRNA expression in morphine-tolerant rats with bone cancer pain.Methods Sixty female SD rats weighing 180-200 g in which intrathecal(IT)catheter was successfully placed at L3,4 interspace without complications were randomly divided into 4 groups:control group(group C,n=10);minocycline group(group M,n=10);bone cancer pain + morphine tolerance group(group BM,n=20)and bone cancer pain+morphine tolerance+ minocycline group(group BM+M,n=20).Bone cancer pain was induced by injection of breast cancer cells(Walker256)10μl(400/μl)into upper segment of bone marrow of right tibia.Morphine tolerance was induced by IT injection of morphine 20 μg/kg twice a day for 7 consecutive days starting from the 10th day after intratibia injection in BM and BM + M groups. Minocycline 0.25 mg/kg was injected IT once a day for 3 consecutive days in group M and after the model of bone cancer pain and morphine tolerance was established in group BM + M. Mechanical withdrawal threshold (MWT) and mechanical withdrawal duration (MWD) were determined before (T0, baseline) and at3, 6 and 9 days after operation (T1-3) and at 4, 7, 10 and 12 days after IT morphine injection was started (T4-7).The animals were sacrificed at T6 and T7 respectively in BM and BM + M groups and at T7 in C and M groups.The lumbar segment of the spinal cord (L4-6) was removed for determination of CX3 CR1 mRNA (by RT-PCR) and OX-42 expression (by immuno-histochemistry) .Results There was no significant difference in MWT and MWD at all time points between group C and group M. MWT was significantly decreased while MWD prolonged in morphine tolerant rats with cancer pain in group BM as compared with C and M groups. The hyperalgesia was significantly attenuated by IT minocycline in group BM + M. Spinal CX3 CR1 mRNA and OX-42 expression was significantly increased in group BM than in C and M groups. IT minocycline attenuated the increase in spinal CX3 CR, mRNA and OX-42 expression induced by bone cancer. Conclusion IT minocycline can inhibit spinal CX3CR1 mRNA expression, thereby antagonizing morphine tolerance in morphine-tolerant rats with bone cancer pain.     

Inhibition of microRNA-19a-3p alleviates the neuropathic pain (NP) in rats after chronic constriction injury (CCI) via targeting KLF7

Background/purposeNeuropathic pain(NP) is derived from the dysfunctions of nerve system. The current research is to explore the impact and mechanism of miR-19a-3p in neuropathic pain in rats.MethodsThe NP was induced through the chronic constriction injury (CCI) surgery in rats. The pro-inflammatory factors (IL-1β, IL-6, TNF-α) in spinal cord tissues from rats were measured using Elisa kits. Moreover, the different levels of thermal hyperalgesia and mechanical allodynia in rats were examined through paw withdrawal latency (PWL) and paw withdrawal threshold (PWT). To investigate into the role of miR-19a-3p and KLF7 in NP of rats, the knockdown of miR-19a-3p alone or along with KLF7 downregulation in rats were achieved through lentivirus injection. The miR-19a-3p and KLF7 expression in spinal cord of rats on Day 3,7,14 after CCI were detected using RT-qPCR. The protein expression of KLF7 were measured by Western blot. Bioinformatics and luciferase assays were used for the prediction and verification of bindings between KLF7 and miR-19a-3p.ResultsCCI surgery caused neuropathic pain in rats with the levels of inflammatory cytokines increased and PWL and PWT decreased. Moreover, miR-19a-3p expression was increased while the protein and mRNA levels were decreased in spinal cord tissues in rats after CCI surgery. In rat microglial cells, miR-19a-3p downregulation could promote the KLF7 in both mRNA and protein expression. In spinal cord tissues of rats, the inhibition of miR-19a-3p enhanced the KLF7 expression. Furthermore, miR-19a-3p downregulation suppressed the IL-1β, IL-6 and TNF-α concentrations, and could decrease the NP but inhibition of KLF7 could partially reverse this in CCI rats.ConclusionmiR-19a-3p inhibition may alleviate NP via KLF7 in CCI rats.     

炎性痛-吗啡耐受大鼠背根神经节辣椒素受体磷酸化水平的变化

目的 探讨炎性痛-吗啡耐受大鼠背根神经节辣椒素受体(VR1)磷酸化水平的变化.方法 鞘内置管成功的成年雄性SD大鼠20只,体重230～250 g,2～3月龄,采用左后足踝关节腔注射完全弗氏佐剂(CFA)50μl的方法制备炎性痛模型.大鼠随机分为4组(n=5),炎性痛+生理盐水组(NS组):注射剂CFA后3 d鞘内注射生理盐水10μl,2次/d,连续7 d;单纯吗啡组(M0组):不建立炎性痛模型,鞘内注射吗啡10μl/kg,2次/d,连续7 d;炎性痛+单次吗啡组(M1组):注射CFA后3 d鞘内注射吗啡10μl/kg;炎性痛+连续吗啡组(M2组):注射CFA后3 d鞘内注射吗啡10 μg/kg,2次/d,连续7 d.于鞘内置管后、注射CFA后3 d鞘内给药前、给药1～7 d测定机械缩足反射阈值和缩足潜伏期,最后一次测定痛阈后处死大鼠,采用Western blot法测定背根神经节磷酸化VR1(p-VR1)的表达水平.结果 NS组和M1组未发生吗啡耐受,M0组和M2组发生吗啡耐受.4组中,M2组背根神经节p-VR1表达水平最高(P＜0.05).结论炎性痛-吗啡耐受大鼠背根神经节VR1磷酸化水平升高,该变化可能是吗啡耐受形成的机制.     

大鼠骨癌痛-慢性吗啡耐受模型的建立

目的 建立大鼠骨癌痛-慢性吗啡耐受模型.方法 鞘内置管成功的成年雌性SD大鼠36只,体重180～200 g,采用随机数字表法,将大鼠随机分为3组(n=12):假手术组(S组)、慢性吗啡耐受组(M组)和骨癌痛+慢性吗啡耐受组(BM组).BM组右侧胫骨上段骨髓腔注入Walker256癌细胞10 μl(4×102个细胞/μl)制备骨癌痛模型,M组注射热灭活的Walker256癌细胞10μl,接种后10 d开始鞘内注射吗啡20μg/kg,2次/d,连续9 d.S组仅暴露右侧胫骨上段.分别于接种Walker256癌细胞前、接种后1、3、6、9 d、给予吗啡1、3、5、7、9 d时测定机械缩足阈值(MWT)和机械缩足持续时间(MWD),并于接种后9 d时行放射学检查,进行骨质破坏评分.最后1次测定痛周后,对右侧足底进行触摸刺激,停止刺激后3 h时取脊髓L4-6节段,测定脊髓背角Foa表达水平.结果 与S组比较,M组MWT降低,MWD延长,脊髓背角Fos表达上调(P＜0.05或0.01);与M组比较,BM组MWT降低,骨质破坏评分升高,MWD延长,脊髓背角Fos表达上调(P＜0.05或0.01).结论 成功制备了大鼠骨癌痛-慢性吗啡耐受模型.

Abstract：

Objective To establish a rat model of bone cancer pain-chronic morphine tolerance. Methods Thirty-six adult female Sprague-Dawley rats weighing 180-200 g in which intrathecal catheters were successfully placed without complications were randomly divided into 3 groups ( n = 12 each) :group sham operation (group S),group chronic morphine tolerance (group M) and group bone cancer pain + chronic morphine tolerance (group BM). Bone cancer pain was induced by intra-tibia inoculation of Walker256 mammary gland carcinoma cells (4 ×102 cells/μl) in group BM, while in group M heat-inactivated Walker256 mammary gland carcinoma cells were given instead, and then 10 days later, intrathecal morphine 20 μg,/kg was administered twice a day for 9 consecutive days. The mechanical paw withdrawal threshold (MWT) and mechanical paw withdrawal duration (MWD) were measured before inoculation, at day 1, 3, 6 and 9 after inoculation, and at day 1, 3, 5, 7 and 9 of morphine administration. The degree of bone destruction was assessed by radiological analysis at day 9 after inoculation. After the last measurement of pain threshold, the rats were given innoxious touch-stimulus. The rats were sacrificed 3 h after stopping the stimulus, and L4-6 segment of the spinal cord was isolated to determine the expression of Fos protein in the spinal dorsal horn. Results Compared with group S, MWT was significantly decreased, MWD was significantly prolonged and the expression of Fos protein was up-regulated in group M ( P ＜ 0.05 or 0.01 ). MWT was significantly decreased, MWD was significantly prolonged, bone destruction scores were significantly increased,and the expression of Fos protein was up-regulated in group BM compared with group M ( P ＜ 0.05 or 0.01 ). Conclusion A rat model of bone cancer pain-chronic morphine tolerance is successfully established.     

慢性吗啡耐受大鼠脊髓神经元兴奋性氨基酸转运体3表达的变化

目的 观察慢性吗啡耐受大鼠脊髓神经元兴奋性氨基酸转运体3(EAAT3)表达的变化.方法 成年雄性SD大鼠45只,随机分为5组(n=9),除假手术组(S组)外,生理盐水组(NS组)、吗啡组(M组)、氯胺酮组(K组)和吗啡+氯胺酮组(M+K组)均进行鞘内置管,鞘内置管后3 d进行鞘内给药,Ns组鞘内注射生理盐水40 μl,M组给予吗啡20μg,K组给予氯胺酮30μg,M+K组给予吗啡20μg+氯胺酮30μg,2次/d,连续7 d.分别在给药前、给药1、3、5、7 d及停药后1 d时测定50%缩爪阈值(PWT)与辐射热缩爪潜伏期(PWL),最后一次测定痛阈后处死大鼠,分别采用免疫印迹分析和免疫组化法检测脊髓EAAT3的表达水平.结果 与S组比较,M组给药1、3 d时PWT升高,给药7 d及停药后1 d时PWT降低,给药1、3、5 d时PWL延长,停药后1 d时PWL缩短;M+K组给药1、3、5、7 d及停药后1 d时PWT升高,PWL延长,M组和M+K组脊髓EAAT3表达下调(P<0.05);与M组比较,M+K组给药3、5、7 d及停药后1 d时PWT升高,给药5、7 d时及停药后1 d时PWL延长.脊髓EAAT3表达上调(P<0.05).EAAT3主要分布于脊髓背角Ⅰ-Ⅱ层的感觉神经元.结论 脊髓背角神经元EAAT3表达下调参与了大鼠慢性吗啡耐受的形成,吗啡下调EAAT3表达的部分机制与激活N-甲基-D天冬氨酸受体有关.