p38MAPK信号转导通路在大鼠内毒素性急性肺损伤中的作用

目的 探讨p38丝裂原活化蛋白激酶(p38MAPK)信号转导通路在大鼠内毒素性急性肺损伤中的作用.方法 成年雄性SD大鼠60只,体重180～230 g,采用随机数字表法,将大鼠随机分为4组:对照组(C组,n=6)、急性肺损伤组(ALI组,n=24)、p38MAPK特异性抑制剂SB203580+ALI组(SB+ALI组,n=24)和SB203580组(SB组,n=6).ALI组尾静脉注射内毒素5 mg/kg制备大鼠急性肺损伤模型,C组给予等容量生理盐水,SB+ALI组于注射内毒素前30 min经尾静脉注射SB20358010 mg/kg.ALI组和SB+ALI组于注射内毒素后1、3、6 h(T1-3)时随机取8只大鼠,C组和SB组分别于给予生理盐水、SB203580后1 h处死取肺组织,检测磷酸化p38MAPK(p-p38MAPK)蛋白表达.T3时回收支气管肺泡灌洗液(BALF),测定蛋白浓度.计算细胞凋亡指数,观察肺组织病理学结果.另取32只大鼠,采用随机数字表法,将大鼠随机分为2组(n=16):ALI组和SB+ALI组,观察48 h内大鼠生存情况.结果 与C组相比,ALI组和SB+ALI组BALF中蛋白浓度、细胞凋亡指数、肺组织p-p38MAPK蛋白表达水平升高(P＜0.05);与ALI组相比,SB+ALI组上述指标降低(P＜0.05).SB+ALI组病理学损伤程度较ALI组明显减轻.ALI组大鼠生存率较SB+ALI组降低(P＜0.01).结论 p38MAPK信号转导通路参与了大鼠内毒素性急性肺损伤的发生和发展,可能与肺组织细胞凋亡有关.

Abstract：

Objective To investigate the role of p38 mitogen-activated protein kinase (MAPK) signal transduction pathway in lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods Sixty male SD rats weighing 180-230 g were randomly divided into 4 groups: control group (group C, n = 6), ALI group ( n = 24),p38MAPK specific inhibitor SB203580 + ALI group (group SB + ALI, n = 24), SB203580 group (group SB,n =6). LPS 5 mg/kg was injected intravenously via tail vein in group ALI and SB + ALI, while the equal volume of normal saline was given instead in group C. Group SB + ALI received iv injection of SB203580 10 mg/kg via tail vein 30 min before LPS administration. Group SB received injection of SB203580. The rats were sacrificed at 1, 3 and6 h agter LPS administration (T1-3) in group ALI and SB + ALI (8 rats at each time point) andat 1 h after administration in C and SB groups. The lungs were immediately removed for microscopic examination and determination of phosphorylated p38MAPK (p-p38MAPK) expression, the concentration of protein in bronchoalveolar lavage fluid (BALF) and apoptotic index (AI). Another 32 rats were selected and randomly divided into 2 groups for survival study: ALI group and SB + ALI group ( n = 16 each), and then they were treated as mentioned above and observed for 48 h. Results The concentration of protein in BALF, AI and p-p38MAPK expression were significantly increased in group ALI and SB + ALI compared with group C, while decreased in group SB + ALI compared with group ALI ( P ＜ 0. 05 ). LPS-induced pulmonary histological changes were significantly attenuated in group SB + ALI compared with group ALI. The survival rate was significantly decreased in group ALI compgred with group SB + ALI ( P ＜ 0.01 ). Conclusion p38 MAPK signal transduction pathway is involved in LPS-induced ALI, which may be related to the apoptosis in the cells in the lung.     

盐酸戊乙奎醚预先给药对脓毒症小鼠急性肺损伤时β-抑制蛋白-1表达的影响

目的 探讨盐酸戊乙奎醚预先给药对脓毒症小鼠急性肺损伤时β-抑制蛋白-1表达的影响.方法 健康雌性昆明小鼠30只,体重18～20 g,采用随机数字表法,将其分为3组(n=10):假手术组(S组)、脓毒症组(CLP组)和盐酸戊乙奎醚组(PHCD组).采用盲肠结扎穿孔法制备脓毒症模型.PHCD组于造模前1h腹腔注射盐酸戊乙奎醚0.45 mg/kg,S组和CLP组给予等容量生理盐水.造模后12 h,收集肺泡灌洗液(BALF),测定总蛋白浓度;取肺组织,行肺损伤评分,测定肺湿/干重(W/D)比和肌球蛋白轻链激酶(MLCK)、血管内皮钙黏蛋白(VE-cadherin)、β-抑制蛋白-1的表达.结果 与S组比较,CLP组和PHCD组肺损伤评分、肺W/D比和BALF总蛋白浓度、肺组织MLCK表达升高,VE-cadherin表达降低,CLP组β-抑制蛋白-1表达降低,PHCD组β-抑制蛋白-1表达升高(P＜ 0.05或0.01);与CLP组比较,PHCD组肺损伤评分、肺W/D比和BALF总蛋白浓度、肺组织MLCK表达降低,VE-cadherin和β-抑制蛋白-1表达升高(P＜0.05或0.01).结论 盐酸戊乙奎醚预先给药可通过上调β-抑制蛋白-1的表达,降低肺微血管通透性,从而减轻脓毒症小鼠急性肺损伤.     

盐酸戊乙奎醚预先给药对脓毒症小鼠急性肺损伤时肺组织β-arrestin-2表达的影响

目的 探讨盐酸戊乙奎醚预先给药对脓毒症小鼠急性肺损伤时肺组织p抑制蛋白-2(β-arrestin-2)表达的影响.方法 健康雌性昆明小鼠30只,6周龄,体重18～20 g,采用随机数字表法,将其随机分为3组(n=10):假手术组(S组)、脓毒症组(CLP组)和盐酸戊乙奎醚预先给药组(PHC组).CLP组和PHC组采用盲肠结扎并穿孔法制备脓毒症模型.PHC组于模型制备前1h时腹腔注射盐酸戊乙奎醚0.45 mg/kg,S组和CLP组于模型制备前1h时腹腔注射等容量生理盐水.模型制备后12h时,采血和收集肺泡灌洗液测定肺通透性指数,采用化学比色法测定肺组织MPO活性,采用ELISA法测定肺组织IL-6含量,采用Western blot法测定肺组织β-arrestin-2蛋白表达,采用RT-PCR法测定肺组织β-arrestin-2 mRNA表达.结果 与S组比较,CLP组肺通透性指数、肺组织MPO活性和IL-6含量均升高,肺组织β-arrestin-2蛋白表达下调,β-arrestin-2 mRNA表达上调(p＜0.05),PHC组肺通透性指数、肺组织MPO活性和IL-6含量均升高,肺组织β-arrestin-2蛋白表达上调,β-arrestin-2 mRNA表达下调(p＜0.05).与CLP组比较,PHC组肺通透性指数、肺组织MPO活件和IL-6含量均降低,肺组织β-arrestin-2蛋白表达上调,β-arrestin-2 mRNA表达下调(P＜0.05).结论 盐酸戊乙奎醚预先给药减轻脓毒症小鼠急性肺损伤的机制可能与上调肺组织β-arrestin-2的蛋白表达有关.     

p38MAPK信号通路在盐酸戊乙奎醚减轻内毒素诱导人脐静脉内皮细胞损伤中的作用

目的 探讨p38丝裂原活化蛋白激酶(p38 MAPK)信号通路在盐酸戊乙奎醚减轻内毒素诱导人脐静脉内皮细胞损伤中的作用.方法 培养人脐静脉内皮细胞,以1×104/ml密度接种于96孔培养板(100μl/孔)或24孔培养板(3 ml/孔),以1×106/ml密度接种于培养瓶(5 ml/瓶),采用随机数字表法,将其随机分为4组(n=23):正常对照组(C组)、脂多糖(LPS)组(L组)、盐酸戊乙奎醚组(P组)和盐酸戊乙奎醚+LPS组(PL组),P组和PL组加入终浓度为2μg/ml的盐酸戊乙奎醚,L组和PL组加入终浓度为1 μg∥ml的LPS,PL组于加入盐酸戊乙奎醚后1h加入LPS.加入LPS后24h时,收集细胞,测定磷酸化p38 MAPK(p-p38 MAPK)和p38 MAPK的表达水平,以二者比值反映p38 MAPK激活程度,并测定细胞活力、NO含量和诱导型一氧化氮合酶(iNOS)表达.结果 与C组比较,L组细胞活力降低,NO、p-p38 MAPK和p38 MAPK激活程度升高,iNOS表达上调(P＜0.01),P组上述指标差异无统计学意义(P＞0.05);与L组比较,PL组细胞活力升高,NO、p-p38 MAPK和p38 MAPK激活程度降低,iNOS表达下调(P＜0.05或0.01).结论 p38 MAPK信号通路参与了盐酸戊乙奎醚减轻内毒素诱导人脐静脉内皮细胞损伤的作用.     

盐酸戊乙奎醚对大鼠创伤性急性肺损伤时细胞凋亡的影响

目的 探讨盐酸戊乙奎醚对大鼠创伤性急性肺损伤时细胞凋亡的影响.方法健康雄性SD大鼠54只,体重225～275kg,采用随机数字表法,将大鼠随机分为对照组(C组)、创伤性急性肺损伤组(ALI组)和盐酸戊乙奎醚组(P组),每组18只.采用自制胸部撞击器撞击大鼠胸壁的方法制备创伤性急性肺损伤模型.P组分别于撞击后即刻、撞击后12 h时腹腔注射盐酸戊乙奎醚2 mg/kg.分别于撞击后3、12、24 h时各组随机取6只大鼠处死取肺,光镜和电镜下观察肺组织病理学结果,TUNEL法测定凋亡细胞,计算凋亡指数,免疫组化法检测Bax和Bcl-2的表达.结果 与C组比较,ALI组和P组各时点肺组织细胞凋亡指数、Bax和Bcl-2的表达水平升高,Bcl-2/Bax比值降低(P＜0.05);与ALI组比较,P组各时点肺组织细胞凋亡指数和Bax表达水平降低,Bcl-2的表达水平和Bcl-2/Bax比值升高(P＜0.01).P组肺组织病理学损伤程度较ALI组减轻.结论 盐酸戊乙奎醚可通过抑制细胞凋亡减轻大鼠创伤性急性肺损伤.

Abstract：

Objective To investigate the effect of penehyclidine hydrochloride on the cell apoptosis in lung tissues in a rat model of traumatic acute lung injury (ALI) .Methods Fifty-four SD rats weighing 225-275 kg were randomly divided into 3 groups ( n = 18 each) : control group (group C) , ALI group, penehyclidine hydrochloride group ( group P) . Traumatic ALI was induced by dropping a self-made impact device on the chest of anesthetized rats according to the technique described by Raghavendran et al. Intraperitoneal penehyclidine hydrochloride 2 mg/kg was injected immediately after blunt chest trauma and at 12 h after blunt chest trauma in group P. Six rats in each group were sacrificed at 3, 12 and 24 h after blunt chest trauma and the lung tissues collected for microscopic examination and determination of cell apoptosis (by TUNEL) and expression of Bax and Bcl-2 (by immuno-histochemical staining) . The apoptosis index was calculated. Results The apoptosis index and expression of Bax and Bcl-2 were significantly higher, while the ratio of Bcl-2/Bax was significantly lower at each time point in groups ALI and P than in group C ( P ＜ 0.05) . The apoptosis index and Bax expression were significantly lower,while the Bcl-2 expression and ratio of Bcl-2/ Bax higher at each time point in group P than in group ALI.The microscopic examination showed that penehyclidine hydrochloride injection significantly attenuated the pathologic changes. Conclusion Penehyclidine hydrochloride can reduce the traumatic ALI through inhibiting the cell apoptosis in rat lung tissues.     

盐酸戊乙奎醚对体外循环致大鼠急性肺损伤的影响

目的 评价盐酸戊乙奎醚对体外循环(CPB)致大鼠急性肺损伤的影响.方法 成年雄性SD大鼠40只,4～6月龄,体重330～420 g,采用随机数字表法,将其随机分为4组(n=10):假手术组(S组)仅进行动脉和静脉穿刺置管;急性肺损伤组(ALI组)、低剂量盐酸戊乙奎醚组(PL组)和高剂量盐酸戊乙奎醚组(PH组)建立CPB模型;PL组和PH组分别在预冲液中加入盐酸戊乙奎醚0.6和2.0 mg/kg,ALI组加入等容量生理盐水,进行CPB1h.于CPB前和CPB结束后2h采集动脉血样,进行血气分析;于CPB结束后2h时采集上腔静脉血样,测定血浆TNF-α和IL-6的浓度;取肺组织测定含水量、MDA含量和谷胱甘肽过氧化物酶(GSH-px)活性,光镜下观察病理学改变.结果 与S组比较,ALI组、PL组和PH组CPB结束后2h时PaO2降低,肺组织含水量、MDA含量和血浆TNF-α和IL-6的浓度升高,肺组织GSH-px活性降低(P＜0.05);与ALI组比较,PL组和PH组CPB结束后2h时PaO2升高,肺组织含水量、MDA含量和血浆TNF-α和IL-6的浓度降低,肺组织GSH-px活性升高(P＜0.05),病理学损伤减轻;与PL组比较,PH组CPB结束后2h时PaO2升高,肺组织含水量、MDA含量和血浆TNF-α和IL-6的浓度降低,肺组织GSH-px活性升高(P＜0.05),病理学损伤减轻更明显.结论 盐酸戊乙奎醚0.6和2.0 mg/kg可减轻CPB致大鼠急性肺损伤,且与剂量有关,其机制与抑制脂质过氧化反应和炎性反应有关.     

P38MAPK信号通路在失血性休克复苏诱发急性肺损伤小鼠HO-1表达上调中的作用

目的 探讨p38分裂原激活蛋白激酶(p38MAPK)信号通路在失血性休克复苏诱发急性肺损伤小鼠血红素加氧酶1(HO-1)表达上调中的作用.方法 SPF级野生型小鼠C3H/HeN32只32只,10～12周龄,体重20～25 g,随机分为4组(n=8),假手术组(S组):只进行手术操作;失血性休克复苏组(HSR组):股动脉放血,至MAP为40 mm Hg,通过放血和回输血液维持MAP 35～45mmHg,60 min后回输全部血液和等失血量的乳酸钠林格氏液复苏;FR167653组(FR组):静脉注射p38MAPK抑制剂FR167653 5 mg/kg;FR+HSR组:于放血前30 min静脉注射FR167653 5 mg/kg.复苏后6 h处死小鼠,取肺组织,观察病理学结果,并进行病理学评分,计算肺湿/干重比,检测肺组织髓过氧化物酶(MPO)、IL-10、IL-6和HO-1水平以及p38MAPK的激活水平.结果 与S组比较,HSR组肺组织病理学评分、肺湿/干重比、MPO、IL-6、IL-10、HO-1和p38MAPK的激活水平升高,HSR+FR组肺组织病理学评分、肺湿/干重比和HO-1表达水平升高(P＜0.01),FR组上述指标差异无统计学意义(P＞0.05);与HSR组比较,HSR+FR组肺组织病理学评分、肺湿/干重比、MPO、IL-6、IL-10、HO-1和p38 MAPK激活水平降低(P＜0.01).结论 p38MAPK信号通路介导了失血性休克复苏诱发急性肺损伤小鼠HO-1的表达上调.     

戊乙奎醚预先给药对大鼠急性肺损伤时NF-κB的影响

目的 探讨戊乙奎醚预先给药对大鼠急性肺损伤(ALI)时NF-κB的影响.方法 雄性SD大鼠35只,体重210～280 g,随机分为5组(n=7):对照组(C组)、ALI组和低、中、高剂量戊乙奎醚组(P1-3组).采用经尾静脉注射内毒素5 mg/kg的方法建立大鼠ALI模型.C组和ALI组经腹腔注射生理盐水0.5 ml,P1～3组分别经腹腔注射戊乙奎醚0.03、0.1和3 mg/kg,30 min后ALI组、P1～3组制备AU模型,C组不制备模型.于静脉注射LPS后4 h时,行血气分析,计算氧合指数;称量肺组织湿重(W)、干重(D),计算W/D;采用比色法测定肺组织髓过氧化物酶(MPO)活性;采用RT-PCR法测定肺组织肿瘤坏死因子-α(TNF-α)mRNA、白细胞介素-1β(IL-1β)mRNA的表达水平;采用ELISA法测定肺组织TNF-α和IL-1β的含量;采用非放射性EMSA法测定肺组织NF-κB活性;采用免疫组织化学法测定肺组织NF-κB的表达水平.结果 与C组比较,其余各组氧合指数降低,肺组织W/D和MPO活性、TNF-α,IL-1β含量及其相应mRNA表达水平、NF-κB活性和表达水平均升高(P<0.05或0.01);与ALI组比较,P1～3组氧合指数升高,肺组织W/D和MPO活性降低,TNF-α、IL-1β含量及其相应mRNA表达水平降低,NF-κB活性和表达水平降低(P<0.05);P1～3组上述指标比较差异无统计学意义(P>0.05).结论 戊乙奎醚预先给药减轻大鼠急性肺损伤的机制可能与抑制NF-κB的活化,下调NF-κB的表达,降低肺组织炎性反应有关.     

c-Jun氨基末端激酶在大鼠内毒素性急性肺损伤中的作用

目的 评价c-Jun氨基末端激酶(JNK)在大鼠内毒素性急性肺损伤中的作用.方法 雄性成年SD大鼠80只,体重250～300 g,采用随机数字表法,将其随机分为4组(n=20):对照组(C组)、急性肺损伤组(ALI组)、SP600125组(S组)和二甲基亚砜组(D组).ALI组、S组和D组尾静脉注射LPS 5 mg/kg,C组尾静脉注射等容量生理盐水;S组和D组给予LPS后,分别尾静脉注射JNK抑制剂SP600125 30 mg/kg或二甲基亚砜0.2 ml.于给予LPS后4 h时,各组处死10只大鼠,回收支气管肺泡灌洗液(BALF)并取肺组织,采用ELISA法检测BALF中TNF-α和IL-1β的浓度,计算肺组织湿重/干重比(W/D比),观察肺组织病理学结果,并进行肺损伤评分.各组其余10只大鼠观察至给予LPS后48 h,记录大鼠生存情况.结果 与C组比较,其余各组BALF中TNF-α和IL-1β的浓度、肺组织W/D比和肺损伤评分升高,生存率降低(P<0.05或0.01);与ALI组比较,S组BALF中TNF-α和IL-1度、肺组织W/D比和肺损伤评分降低,生存率升高(P<0.01),D组差异无统计学意义(P>0.05).结论 JNK的活化参与了大鼠内毒素性急性肺损伤的发生发展.

Abstract：

Objective To evaluate the role of c-Jun N-terminal kinase (JNK) in lipopolysaccharide (LPS)-induced acute lung injury ( ALI) in rats.Methods Eighty male SD rats weighing 250-300 g were randomly divided into 4 groups ( n = 20 each) : control group (group C) ; ALI group; LPS + SP600125 (JNK inhibitor)group (group S) and LPS+ DMSO (the solvent) group (group DMSO) . ALI was induced by intravenous LPS 5mg/kg. In S and DMSO groups, SP600125 30 mg/kg and DMSO 0.2 ml were injected intravenously after LPS administration respectively. Ten animals were sacrificed by exsanguinafions at 4 h after LPS administration in each group. The broncho-alveolar lavage fluid (BALF) was colleted. The TNF-α and IL-1β concentrations in BALF were measured. The lungs were removed for microscopic examination and determination of W/D lung weight ratio. The other 10 animals in each group were observed for 48 h survival rate. Results Intravenous LPS significantly increased TNF-α and IL-1β concentrations in BALF and W/D lung weight ratio, decreased 48 h survival rate and induced histologic damage. Intravenous SP600125 30 mg/kg significantly attenuated the above-mentioned LPS-induced changes. Conclusion Activation of JNK is involved in the development of endotoxin-induced ALI in rats.     

盐酸戊乙奎醚预先给药对大鼠内毒素性急性肺损伤的影响

目的研究盐酸戊乙奎醚预先给药对内毒素诱导大鼠急性肺损伤(ALI)的影响及其机制。方法40只雄性SD大鼠随机分为5组(n=8),对照组(C组):腹腔和尾静脉均注射生理盐水1 ml/kg;模型组(L组):腹腔注射生理盐水1 ml/kg,30 min后经尾静脉注射脂多糖(LPS)5mg/kg;盐酸戊乙奎醚低剂量组(DL组)、中剂量组(DM组)和高剂量组(DH组)分别腹腔注射盐酸戊乙奎醚0.03 mg/kg、0.1 mg/kg、0.3 mg/kg,30 min后经尾静脉注射LPS 5 mg/kg。LPS注射后4 h放血处死动物。检测肺组织湿/干重比(W/D)、肺通透性指数(LPI)、髓过氧化物酶(MPO)活性、丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性;检测支气管肺泡灌洗液蛋白浓度、乳酸脱氢酶(LDH)活性和中性粒细胞数;测定血清MDA水平和SOD活性;光镜观察肺组织形态学改变;电镜观察肺组织超微结构。结果与C组比较, L组、DL组、DM组和DH组肺W/D、肺含水量、LPI、支气管肺泡灌洗液LDH活性增加,支气管肺泡灌洗液中性粒细胞数和肺组织MPO活性、肺组织和血清MDA水平升高,SOD活性降低(P<0.05);与L组相比,DL组、DM组和DH组肺W/D、肺含水量、LPI、支气管肺泡灌洗液LDH活性降低,支气管肺泡灌洗液中性粒细胞数和肺组织MPO活性以及肺组织和血清MDA水平降低,SOD活性升高(P<0.05); DL组、DM组和DH组各指标组间差异无统计学意义(P>0.05)。光镜、电镜观察:盐酸戊乙奎醚预先给药各组肺组织病理学变化较L组减轻。结论盐酸戊乙奎醚预先给药可减轻内毒素诱导的大鼠急性肺损伤。     

戊乙奎醚对肢体缺血再灌注诱发大鼠肺损伤的影响

目的 探讨戊乙奎醚对肢体缺血再灌注诱发大鼠肺损伤的影响.方法 雄性Wistar大鼠36只,体重250～300 g,随机分为4组(n=9):对照组(Ⅰ组)、肢体缺血再灌注诱发肺损伤组(Ⅱ组)、小剂量盐酸戊乙奎醚组(Ⅲ组)和大剂量盐酸戊乙奎醚组(Ⅳ组).Ⅱ组、Ⅲ组和Ⅳ组麻醉后双后肢缺血3 h,Ⅲ组和Ⅳ组分别于股动脉开放前10 min肌肉注射盐酸戊乙奎醚2、9 mg/kg,再灌注4 h快速取肺,计算肺组织湿/干重比(W/D),透射电镜下观察肺组织超微结构,酶联免疫吸附法测定肺组织肿瘤坏死因子-α(TNF-α)和白细胞介素(IL)-10含量.结果 与Ⅰ组比较,Ⅱ组肺组织W/D及TNF-α、IL-10含量升高(P<0.01);与Ⅱ组比较,Ⅲ组肺组织W/D及TNDF-α含量降低、IL-10含量升高(P<0.01);与Ⅲ组比较,Ⅳ组肺组织W/D及TNF-α含量降低、IL-10含量升高(P<0.01).结论 戊乙奎醚可减轻肢体缺血再灌注诱发大鼠肺损伤,且呈剂量依赖性,其机制与降低肺组织炎性反应有关.     

糖皮质激素受体在大鼠内毒素性急性肺损伤中的作用

目的 评价糖皮质激素受体(GR)在大鼠内毒素性急性肺损伤中的作用及可能机制.方法 成年雄性SD大鼠60只,体重180 ～ 230 g,采用随机数字表法,将其随机分为4组:对照组(C组,n=6)、RU486组(GR特异性拮抗剂组,R组,n=6)、急性肺损伤组(ALI组,n=24)、RU486+ ALI组(RA组,n=24).ALI组尾静脉注射内毒素(LPS)5 mg/kg制备大鼠急性肺损伤模型,C组给予等容量生理盐水,R组皮下注射GR拮抗剂RU486 20 mg/kg,RA组注射RU486 20 mg/kg 90 min后注射LPS.ALI组及RA组分别于注射LPS后1、3和6 h(T1～3)时,各组随机取8只大鼠,C组与R组于注射生理盐水、RU486 1 h后处死取肺,检测p-p38MAPK、丝裂原活化蛋白激酶磷酸酶-1(MKP-1)的表达.T3时回收支气管肺泡灌洗液(BALF),测定蛋白和TNF-α的浓度;计算细胞凋亡指数;观察肺组织病理学结果.另取32只大鼠,体重180 ～ 230 g,采用随机数字表法,将其随机分为2组(n=16):急性肺损伤组(ALI1组)、RU486+ ALI组(RA1组),处理方法同上.观察48 h内大鼠生存情况.结果 与C组相比,ALI组、RA组BALF蛋白浓度和TNF-α浓度、细胞凋亡指数升高(P＜0.05)、病理学损伤加重;T1～3时p-p38MAPK表达上调,ALI组T2,3时MKP-1表达下调,RA组T1-3时MKP-1表达下调(P＜0.05);与ALI组相比,RA组BALF蛋白浓度和TNF-α浓度、细胞凋亡指数增加,T1～3时p-p38MAPK表达上调(P＜0.05),T2.3时MKP-1表达差异无统计学意义(P＞0.05),RA1组大鼠生存率低于ALI1组(P＜0.05).结论 GR参与大鼠内毒素急性肺损伤的发生发展,其机制与抑制p38MAPK信号转导通路,降低肺组织细胞凋亡有关.     

盐酸戊乙奎醚对大鼠胸部撞击致急性肺损伤及肺组织Toll样受体4表达的影响

目的 探讨盐酸戊乙奎醚对大鼠胸部撞击致急性肺损伤及肺组织Toll样受体4(TLR4)表达的影响.方法 健康雄性SD大鼠96只,体重250～300 g,采用随机数字表法,将大鼠随机分为3组(n=32):对照组(C组)只麻醉,不制备模型;肺损伤组(ALI组);盐酸戊乙奎醚组(PHcD组)模型制备后即刻,腹腔注射盐酸戊乙奎醚2 mg/kg.砝码(300g)于95 cm高处自由落体撞击大鼠心前区以制备急性肺损伤模型.于模型制备后2、8、12和24h时取8只大鼠,取动脉血样,测定血清TNF-α浓度.于模型制备后8 h取8只大鼠,取动脉血样,行动脉血气分析,随后处死大鼠,取肺组织观察病理学结果,测定干/湿重比(W/D比)、髓过氧化物酶(MPO)活性和TLR4表达水平.结果 与c组比较,ALI组和PHCD组pH值和PaO2下降,PaCO2、乳酸浓度、肺组织MPO活性、W/D比及TLR4表达和血清TNF-α浓度升高(P＜0.01);与ALI组比较,PHcD组pH值和PaO2升高,PaCO2、乳酸浓度、肺组织MPO活性、W/D比及TLR4表达和血清TNF-α浓度降低(P＜0.05).PHcD组肺组织病理性损伤较ALI组减轻.结论 盐酸戊乙奎醚可减轻大鼠胸部撞击诱发的急性肺损伤,其机制与下调肺组织TLR4表达,降低炎性反应有关.

Abstract：

Objective To investigate the effects of penehyclidine hydrochloride (PHCD) on acute lung injury (ALI) induced by blunt chest trauma and Toll-like receptor 4 (TLR4) expression in the lung tissues in rats.Methods Ninety-six male SD rats weighing 250-300 g were randomly divided into 3 groups ( n = 32 each):control group (group C), ALI group and PHCD group. ALI was induced by dropping a 300 g weight onto a precordial protective shield to direct the impact force away from the heart and toward the lungs in anesthetized rats according to the method described by Raghavendran et al. PHCD 2 mg/kg was injected intraperitoneally immediately after ALI was induced in group PHCD. Eight rats were selected at 2, 8, 12 and 24 h after ALI was induced, and arterial blood samples were collected for determination of the serum TNF-α concentration. Eight rats were selected at 8 h after ALI was induced, arterial blood samples collected for blood gas analysis and then the rats sacrificed. The lungs were immediately removed for determination of W/D lung weight ratio, myeloperoxidase (MPO) activity and TLR4 expression, and microscopic examination. Results The pH value and PaO2 were significantly lower, and the PaCO2, lactic acid level, MPO activity, W/D ratio, TLR4 expression and serum TNF-α concentration higher in groups ALI and PHCD than in group C (P ＜ 0.01 ). The pH value and PaO2 were significantly higher, and the PaCO2, lactic acid level, MPO activity, W/D ratio, TLR4 expression and serum TNF-α concentration lower in group PHCD than in group ALI ( P ＜ 0.05). The lung histopathologic damage was significantly ameliorated in PHCD group as compared with ALI group. Conclusion PHCD can protect the lungs against blunt chest trauma-induced ALI, and the down-regulation of TLR4 expression in lung tissues and reduction of inflammatory response are involved in the mechanism.     

p38MAPK信号通路在内毒素性休克诱发急性肺损伤大鼠肺组织HO-1表达上调中的作用

目的 评价p38丝裂原活化蛋白激酶(p38MAPK)信号通路在内毒素性休克诱发急性肺损伤大鼠肺组织血红素加氧酶-1(HO-1)表达上调中的作用.方法 雄性SD大鼠48只,8周龄,体重180～ 200g,采用随机数字表法,将其随机分为4组(n=12):对照组(C组)、内毒素性休克组(LS组)、内毒素性休克+ p38MAPK特异性抑制剂SB203580组(LSS组)和SB203580组(SB组).C组和SB组股静脉注射生理盐水0.5 ml;LS和LSS组股静脉注射LPS 10 mg/kg(溶于0.5ml生理盐水)；2h内MAP下降至基础值的75％时,C组和IS组股静脉输注10％二甲基亚砜0.1ml；LSS组和SB组股静脉输注SB203580 5 μmol/kg(溶于0.1 ml 10％二甲基亚砜),输注速率0.01 ml/min.给予LPS或生理盐水后6h时采集动脉血样,进行血气分析,计算氧合指数(PaO2/FiO2)；然后处死大鼠取肺组织,光镜下观察病理学结果,并进行病理学损伤评分,计算肺含水率,测定SOD活性、MDA含量、HO-1 mRNA及其蛋白、p38MAPK蛋白和磷酸化p38MAPK(p-p38MAPK)蛋白的表达.结果 与C组比较,IS组和LSS组氧合指数和SOD活性降低,病理学损伤评分、肺含水率和MDA含量升高,肺组织HO-1 mRNA及其蛋白和p-p38MAPK蛋白的表达上调(P＜0.05),p38MAPK蛋白表达差异无统计学意义,SB组各指标差异无统计学意义(P＞0.05)；与LS组比较,LSS组氧合指数和SOD活性升高,病理学损伤评分、肺含水率和MDA含量降低,肺组织HO-1 mRNA及其蛋白表达上调,p-p38MAPK蛋白表达下调(P＜0.05),p38MAPK蛋白表达差异无统计学意义(P＞0.05).结论 抑制p38MAPK信号通路可导致内毒素性休克诱发急性肺损伤大鼠肺组织HO-1表达上调.