创伤后应激障碍模型大鼠内侧前额皮质磷酸化细胞外信号调节激酶1/2及c-fos的变化

目的探讨创伤后应激障碍(PTSD)模型大鼠内侧前额皮质(mPFC)磷酸化细胞外信号调节激酶1/2(pERK1/2)和c-fos的表达变化。方法将30只成年健康雄性Wistar大鼠随机分为对照组(15只)和PTSD模型组(15只),采用无连续单一应激(SPS)方法制备PTSD模型。用免疫组织化学和免疫印迹法检测mPFCpERK1/2的表达变化,RT-PCR检测c-fosmRNA表达变化。结果免疫组织化学分析显示,对照组和模型组pERK1/2阳性细胞数分别为10.4±2.07、48.8±10.08,阳性信号吸光度值分别为24.955±3.691、110.810±10.643,差异有统计学意义(P0.01);免疫印迹分析显示,对照组和模型组pERK/2相对表达量分别为0.510±0.052和1.109±0.106,差异有统计学意义(P0.01);RT-PCR分析结果显示,对照组和模型组c-fosmRNA相对表达分别为0.267±0.067和1.049±0.131,差异有统计学意义(P0.01)。结论mPFCpERK1/2和c-fos表达增高,可能参与了PTSD模型大鼠的病理生理过程。     

慢性强迫游泳应激大鼠内侧前额皮质磷酸化细胞外信号转导激酶1/2的变化

目的探讨慢性强迫游泳应激模型大鼠内侧前额皮质(mPFC)磷酸化细胞外信号转导激酶1/2(pERK1/2)的表达变化。方法将30只成年健康雄性Wistar大鼠随机分为对照组(15只)和慢性强迫游泳应激组(15只)。慢性强迫游泳组连续给予28d的强迫游泳,制备慢性强迫游泳应激模型;通过糖水偏好实验、开场实验和Morris水迷宫检测大鼠抑郁行为学的改变;采用免疫组织化学、免疫印迹法检测mPFC中pERK1/2的表达变化。结果慢性强迫游泳应激组糖水消耗量和糖水偏好百分比分别为(4.114±0.644)%、(86.610±4.450)%,对照组为(8.157±1.105)%、(94.930±2.893)%,差异有统计学意义(P0.01);开场实验中慢性强迫游泳应激组和对照组的直立次数分别为1.75±0.96、6.00±0.82,差异有统计学意义(P0.05);水迷宫实验逃避潜伏期分别为(20.762±3.236)s、(5.632±1.065)s,差异有统计学意义(P0.01);免疫组织化学分析显示,对照组和模型组pERK1/2阳性细胞阳性信号吸光度值分别为47.594±5.355和110.810±10.643,差异有统计学意义(P0.01);免疫印迹法分析结果显示,对照组和模型组pERK/2分别占总ERK1/2的0.216±0.029和0.870±0.066,差异有统计学意义(P0.01)。结论慢性强迫游泳应激能诱发大鼠抑郁症状,促进mPFCpERK1/2表达。     

创伤后应激障碍模型大鼠内侧前额皮质磷酸化细胞外信号调节激酶1/2及EM>c-fos/EM>的变化

目的 探讨创伤后应激障碍（PTSD）模型大鼠内侧前额皮质（mPFC）磷酸化细胞外信号调节激酶1/2（pERK1/2）和c-fos的表达变化。 方法 将30只成年健康雄性Wistar大鼠随机分为对照组（15只）和PTSD模型组（15只）,采用无连续单一应激（SPS）方法制备PTSD模型。用免疫组织化学和免疫印迹法检测mPFC pERK1/2的表达变化,RT-PCR检测c-fos mRNA表达变化。 结果 免疫组织化学分析显示,对照组和模型组pERK1/2阳性细胞数分别为10.4±2.07、48.8±10.08,阳性信号吸光度值分别为24.955±3.691、110.810±10.643,差异有统计学意义（P<0.01）;免疫印迹分析显示,对照组和模型组pERK/2相对表达量分别为0.510±0.052和1.109±0.106,差异有统计学意义（P<0.01）;RT-PCR分析结果显示,对照组和模型组c-fos mRNA相对表达分别为0.267±0.067和1.049±0.131,差异有统计学意义（P<0.01）。 结论 mPFC pERK1/2和c-fos表达增高,可能参与了PTSD模型大鼠的病理生理过程。     

创伤后应激障碍大鼠前额叶内侧皮质糖皮质激素受体表达增高

目的 观察创伤后应激障碍（PTSD）大鼠前额叶内侧皮质（mPFC）神经元糖皮质激素受体（GR）表达的变化。 方法 采用单一连续应激(SPS)方法建立PTSD大鼠模型,取成年健康雄性Wistar大鼠90只,随机分为PTSD模型1d、7d、14d、28d和正常对照组。采用免疫组织化学、免疫印迹和RT-PCR方法分别进行各组mPFC神经元GR表达变化的观察及检测,进行图像分析和统计学处理。结果PTSD大鼠mPFC神经元GR的表达高于对照组,SPS后14d最高,SPS后28d恢复性下调,但仍然高于对照组(P<0.05)。结论PTSD模型大鼠经SPS处理后,mPFC区域出现GR表达的增高。     

痹肿消汤干预胶原诱导关节炎模型大鼠关节滑膜组织细胞外信号调节激酶1/2及细胞外信号调节激酶5的表达

背景：滑膜细胞信号转导异常是类风湿性关节炎的重要发病机制之一。中药复方痹肿消汤治疗类风湿性关节炎具有较好的临床疗效,但在细胞信号转导水平探讨痹肿消汤治疗类风湿性关节炎的作用机制是十分必要的。 目的：观察中药复方痹肿消汤对胶原诱导关节炎模型大鼠滑膜细胞外信号调节激酶1/2,5表达的影响。 方法：SD大鼠45只随机数字表法分为对照组、模型组、痹肿消汤组。胶原诱导关节炎模型大鼠,用痹肿消汤药液3.0~3.5 mL灌胃,1次/d,连续14 d。检测造模后第14,21,28天大鼠滑膜细胞外信号调节激酶1/2,5的磷酸化水平。 结果与结论：造模后,大鼠滑膜细胞外信号调节激酶1/2,5的磷酸化表达随时间而增加(P < 0.05)。痹肿消汤治疗后,细胞外信号调节激酶1/2,5磷酸化表达水平则明显下降(P < 0.05)。提示痹肿消汤能抑制细胞外信号调节激酶1/2,5蛋白激酶的激活,从而抑制细胞外信号调节激酶1/2, 5信号转导通路的活化,这可能是其阻抑类风湿性关节炎滑膜异常增殖、关节骨质侵蚀的重要机制之一。     

细胞外信号调节激酶在偏头痛大鼠模型中的表达

目的探讨细胞外信号调节激酶(ERK)信号转导通路在偏头痛大鼠模型中的作用。方法 48只雄性SD大鼠分为正常对照组、生理盐水对照组和模型组,采用皮下注射硝酸甘油(GTN)法制做大鼠偏头痛模型。应用免疫组化技术及Western印迹法,分别观察各组大鼠硬脑膜、三叉神经节(TG)及三叉神经颈复合体细胞外信号调节激酶(ERK)、磷酸化ERK(p-ERK)的表达。结果 ERK、p-ERK在各组大鼠硬脑膜、三叉神经节及三叉神经颈复合体细胞中均呈阴性表达,模型组大鼠p-ERK表达水平明显高于生理盐水对照组及正常对照组(P<0.05)。结论偏头痛大鼠p-ERK过表达,ERK可能参与了偏头痛痛觉信号的传导,在偏头痛发病机制中发挥作用。     

细胞外信号调节激酶/miR-133b在甲基苯丙胺致PC12细胞神经毒性的作用及机制

目的 探讨甲基苯丙胺(MA)致神经细胞毒性过程中细胞外信号调节激酶(ERK)和miR-133b的表达变化及调控机制。方法 用MA建立PC12神经细胞损伤模型,采用四甲基偶氮唑盐(MTT)检测细胞活性及镜下形态观察确定MA最佳损伤浓度;应用流式细胞术检测细胞内活性氧（ROS）水平;通过 Western blotting技术测定总ERK1/2和磷酸化ERK1/2 (p-ERK1/2)的表达变化;并应用实时定量聚合酶链反应（Real-time PCR）测定miR-133b的表达变化。为进一步分析ERK/miR133b分子通路的作用关系,经U0126特异阻断ERK通路,检测miR-133b的表达变化。 结果 给予不同浓度的MA,均可导致PC12细胞损伤,其中800μmol/L MA处理后,大部分胞体变圆,神经突起退缩,神经网络消失。MTT结果显示细胞活性明显下降。进一步的细胞毒性机制分析显示,MA处理后,细胞内ROS水平升高,p-ERK表达增高,miR-133b表达降低;并且给予ERK通路抑制剂U0126（10μmol/L）后,miR-133b表达升高,细胞活性增强,胞内ROS水平降低,镜下细胞损伤改善。 结论 MA可通过上调ERK磷酸化抑制miR-133b表达,介导神经元毒性损伤。     

细胞外信号调节激酶在三叉神经痛动物模型中的表达

为了研究细胞外信号调节激酶(ERK)信号转导通路在三叉神经痛动物模型中的表达,将24只雄性SD大鼠分为三叉神经痛模型组和对照组两组,模型组大鼠以铬制羊肠线疏松结扎大鼠一侧眶下神经,对照组大鼠眶下神经不结扎。应用免疫组化和免疫荧光染色方法,分别检测大鼠三叉神经节(TG)和三叉神经脊束核尾侧亚核(Vc)中磷酸化ERK(p-ERK)的表达。本研究发现p-ERK在模型组和对照组大鼠的TG和Vc中均有不同程度的表达,但模型组大鼠中p-ERK表达明显高于对照组(P<0.05)。提示ERK可能参与了三叉神经痛(TGN)痛觉信号的传导,在三叉神经痛的发病机制中发挥重要的作用。     

细胞外调节蛋白激酶信号通路参与机械牵张诱导肺泡上皮细胞高迁移率族蛋白B1的表达调控

目的 探讨细胞外调节蛋白激酶（ERK）信号通路在机械牵张诱导肺泡上皮细胞（A549）表达高迁移率族蛋白B1（HMGB1）中的作用。 方法 肺泡上皮细胞A549分为A、B、C 3组,A组为对照组;B组A549细胞施加14%牵张应变,牵张时间为4 h;C组细胞的牵张模式与B组相同,只是于施加牵张前用ERK的特异性抑制剂PD98059预处理A549细胞2h。分别用免疫细胞化学染色和RT-PCR检测细胞HMGB1蛋白和mRNA的表达,用Western blotting检测ERK激酶的活性。 结果 A549细胞施加14 %牵张应变后,HMGB1蛋白和mRNA表达明显增加,ERK激酶活性明显增高（P＜0.05）;该诱导激活作用可被PD98059阻断。 结论 机械牵张通过ERK信号通路,调节A549细胞的HMGB1基因和蛋白表达。     

吗氯贝胺早期干预对创伤后应激障碍大鼠行为及前额皮质pCREB水平的影响

目的探讨吗氯贝胺(Moclobemide,Moc)早期干预对创伤后应激障碍(posttraumatic stress disorder,PTSD)模型大鼠行为及内侧前额皮质pCREB水平的影响。方法采用单一连续刺激(single prolonged stress,SPS)建立大鼠PTSD模型。取成年健康雄性Wistar大鼠48只,随机分为N+sham组(正常对照组),SPS+sham组(SPS刺激后腹腔注射与抑制剂等体积的生理盐水),SPS+Moc组(SPS刺激后腹腔注射吗氯贝胺),N+Moc组(正常大鼠腹腔注射吗氯贝胺)。吗氯贝胺按8mg/kg腹腔注射给药,每日一次,连续14d。采用旷场试验和高架十字迷宫检测大鼠行为表现,并于行为学实验完成后处死大鼠,取前额内侧皮质,采用Western blot检测pCREB的表达水平。结果SPS引起大鼠进入中央区次数减少和总的运动距离缩短,给予Moc后大鼠进入中央区次数增多和总的运动距离增加。SPS引起大鼠进入开臂次数的百分比和开臂停留时间百分比均显著降低,给予Moc后大鼠进入开臂次数的百分比和开臂停留时间百分比明显升高。SPS引起大鼠内侧前额皮质pCREB的表达水平降低,Moc干预后pCREB的表达量增加。结论吗氯贝胺对PTSD大鼠行为改善的作用,可能是与上调前额内侧皮质pCREB水平相关。     

神经病理痛模型大鼠前扣带皮层不同水平磷酸化细胞外信号调节激酶表达差异比较

目的探讨痛相关情绪模型大鼠前扣带皮层(ACC)磷酸化细胞外信号调节激酶(p-ERK)的分布特点。方法将12只雄性SD大鼠随机分为对照组和模型组。模型组大鼠进行右侧腰5脊神经结扎制做模型。采用右后足跖机械痛阈检测观察行为变化,旷场实验和高架O迷宫实验检测痛相关情绪变化,免疫荧光技术检测同侧前扣带皮层前囟前3.2、2.7及2.2mm 3个水平p-ERK表达。结果大鼠经神经病理痛模型制做成功后机械痛阈显著下降,焦虑样行为产生。前扣带皮层前囟前3.2、2.7及2.2mm水平p-ERK阳性细胞表达量分别为11.89±2.57、32±4.67和17.56±2.04。对照组相应的p-ERK阳性细胞表达量分别为12.44±2.16、10±0.87和10.11±1.36。除前囟前3.2mm水平对照组与模型组相比没有显著性差异(P0.05)之外,其他两个水平p-ERK阳性细胞表达量模型组显著高于对照组(P0.01)。结论神经病理性疼痛能诱发大鼠焦虑情绪的产生及ACC脑区pERK的表达增高,这种变化可能主要与ACC脑区前囟前2.7及2.2mm水平p-ERK的变化相关,而与前囟前3.2mm水平无关。     

The role of protein kinase C in the regulation of extracellular signal-regulated kinase by the T cell antigen receptor

The aim of this study was to explore the role of protein kinase C (PKC) in the activation of mitogen-activated protein kinases (MAPK) in T lymphocytes. The MAPK extracellular signal-regulated kinase-2 (ERK2) is activated in response to phorbol esters which stimulate PKC, by transient expression of a constitutively active ras mutant, by cell activation via the G protein-coupled type 1 muscarinic acetylcholine receptor (HM1R) or in response to triggering of the T cell antigen receptor (TCR). The relative contribution of PKC to TCR and HM1R regulation of ERK2 was explored by examining the effects of a PKC inhibitor (Ro 31-8425) on ERK2 activation. The data demonstrate that phorbol ester and HM1R regulation of ERK2 was prevented by the PKC inhibitor, but that the inhibitor had no effect on ERK2 activation induced by expression of a constitutively active ras mutant p21v-Ha-ras. Furthermore, the TCR stimulates both PKC and p21^ras but TCR regulation of ERK2 was only weakly suppressed by the PKC inhibitor. These data indicate that PKC has a potential but not a predominant role in TCR regulation of ERK2.     

Involvement of extracellular signal-regulated protein kinase in acute cocaine-induced c-fos in nucleus accumbens

It is well known that acute cocaine administration increases c-Fos expression that is involved in cocaine-induced persistent changes in the central nervous system. In the present study, we investigated a possible involvement of extracellular signal-regulated protein kinase (ERK) in induction of c-fos expression in response to acute cocaine treatment in nucleus accumbens (NAc). We found that inhibition of ERK activation significantly attenuated cocaine-induced c-fos expression at both protein and mRNA levels in the NAc. Furthermore, using an immunofluorescent staining approach, we found that inhibition of ERK activation completely abolished cocaine-induced increase in number of c-Fos-positive cells in the core region of NAc, whereas, in shell region of NAc, inhibition of ERK activation partially attenuated cocaine-induced c-Fos expression. Our findings suggest that ERK might participate in cocaine-induced c-fos expression in the NAc, particularly in the core region of NAc.     

Oseltamivir (Tamiflu) increases dopamine levels in the rat medial prefrontal cortex

Oseltamivir (Tamiflu), a neuraminidase inhibitor, is effective for treating both seasonal flu and H5N1 influenza A virus infection. Oseltamivir is generally well tolerated, and its most common adverse effects are nausea and vomiting. However, neuropsychiatric behaviors including jumping and falling from balconies by young patients being treated by oseltamivir have been reported from Japan; this has led to warnings against its prescribing by many authorities. The pharmacological mechanism of the neuropsychiatric effects of oseltamivir remains unclear. Many studies reported that changes in neurotransmission and abnormal behaviors are closely related. We investigated the changes in dopamine and serotonin metabolism after systemic administration of oseltamivir in the medial prefrontal cortex (mPFC) of rats by using microdialysis. After systemic administration of oseltamivir (25mg/kg or 100mg/kg; intraperitoneally (i.p.)), extracellular dopamine in the mPFC was significantly increased as compared to the control values; 3,4-dihydroxyphenylacetic acid and homovanillic acid, the metabolites of dopamine, had also increased significantly. Serotonin was unchanged after the administration of oseltamivir. These findings suggest that oseltamivir increased dopamine release in the mPFC; further, they suggest that the increase in dopamine during oseltamivir treatment may have caused abnormal behaviors in young patients. In cases where oseltamivir is prescribed to children, close observation is required.     

外周注射福尔马林诱导大鼠前扣带皮层中ERK-CREB的激活

目的研究外周福尔马林刺激诱导的大鼠前扣带皮层中细胞外信号调节激酶（ERK）和cAMP反应元件结合蛋白（CREB）的激活。方法大鼠单侧足底皮下注射5％的福尔马林,在刺激后的不同时间点将大鼠进行灌注固定或直接取前扣带皮层组织,用免疫组织化学和Western blotting方法观察前扣带皮层中磷酸化ERK和磷酸化CREB的激活情况。结果单侧足底皮下注射福尔马林能诱导双侧前扣带皮层中ERK和CREB的磷酸化。磷酸化的ERK和磷酸化CREB的表达高峰分别在刺激后的3min和30min。非磷酸化的CREB和ERK没有显著变化。结论大鼠前扣带皮层能够接受外周伤害性信息的传人,激活的ERK和CREB可能与疼痛的原发性不愉快有关。     

Inhibitory effect of ketamine on phosphorylation of the extracellular signal-regulated kinase1/2 following brain ischemia and reperfusion in rats with hyperglycemia

To determine if the inhibitory effects of ketamine on the extracellular signal-regulated kinase (ERK) 1/2 are involved in reduction of the hyperglycemia-exaggerated cerebral ischemic lesion, rats with normoglycemia, hyperglycemia, or hyperglycemia supplemented with ketamine were subjected to 15 min of forebrain ischemia, and then, reperfusion for 0.5, 1, and 3h. Phosphorylation of ERK1/2 in the brain tissues was assessed by immunohistochemistry and Western blot analysis. In rats with normoglycemia, we demonstrated a moderate increase of the ERK1/2 phosphorylation in the cingulum cortex and hippocampus CA3 following an ischemic intervention. It quickly dropped to control levels after reperfusion for 0.5h. In rats with hyperglycemia, however, the increase of the ERK1/2 phosphorylation in these areas was significantly higher in all animals reperfused. The neuronal death, detected by the TdT-mediated-dUTP nick end labeling assays, was found in the cingulum cortex (5.23+/-2.34, per high power feild) and hippocampus CA3 areas (6.29+/-3.68, per 1mm(2)) in hyperglycemic group after reperfusion for 3h. With ketamine treatment, the ERK1/2 phosphorylation in cingulum cortex and hippocampus CA1 and CA3 areas was found to be the same as that in normoglycemia rats. Our results suggest that hyperglycemia may increase the ischemic insult through modulation of the signal transduction pathways involving ERK1/2. The inhibitory effects of ketamine on the hyperglycemia-activated ERK1/2 phosphorylation are probably through inhibition of the N-methyl d-aspartate-mediated calcium influx, which subsequently reduce the hyperglycemia-exaggerated cerebral damage.