鹅膏毒肽染毒后大鼠肺表面活性物质的测定

【目的】实验观察鹅膏毒肽染毒后大鼠肺表面活性物质（PS）中磷脂（PL）的组分[磷脂酰甘油（PG）、磷脂酰肌醇（PI）、磷脂酰乙醇胺（PE）]和蛋白质含量的变化.寻找鹅膏毒肽中毒早期敏感特征性标志物.【方法】24只大鼠气管内滴注鹅膏毒肽（0.1 mg/kg,0.4 mg/kg）建立肺损伤模型.分别设12 h、2 d、3 d、5 d组.大鼠的肺组织块分别行HE染色电镜观察,测定支气管液中PL组分和蛋白质含量.【结果】实验组大鼠肺均可见PS层丧失连续、均匀的绒状结构,脱落入肺泡腔,以12 h组较明显.PS中PL（PG和PI）含量增加（P〈0.01）,以12 h组较明显.PS中蛋白质含量最高,以2 d组较明显.【结论】鹅膏毒肽中毒后PS的质与量的变化能较特异的反映肺损伤.测定PL含量是判断肺早期损伤的方法.PL中的PG和PI可能是鹅膏毒肽中毒早期敏感特征性标志物.     

比格犬致命鹅膏急性肝毒性实验研究

目的 建立比格犬致命鹅膏(Amanita exitialis)急性肝毒性模型,探讨含鹅膏肽类毒素蘑菇急性中毒性肝功能衰竭的特点,以期为含鹅膏肽类毒素的蘑菇中毒实验研究提供帮助.方法 UPLC-MS/MS(超高效液相色谱串联质谱)法测定致命鹅膏干粉中鹅膏肽类毒素含量,胶囊喂饲比格犬60 mg/kg体质量致命鹅膏干粉,观察其变化,通过检测凝血及肝肾功能、肝脏病理以及血浆和尿液中鹅膏肽类毒素含量,用于比格犬致命鹅膏急性肝毒性模型观测指标.结果 本研究所用致命鹅膏干粉中鹅膏肽类毒素总含量为(3 482.6±124.94) mg/kg.模型犬在12～48 h出现呕吐、腹泻等症状,染毒后24h,模型犬ALT、AST、TBIL、ALP、PT和APTT水平出现明显升高,染毒后36 h,ALT、AST、PT和APTT水平达到峰值[(ALT (283.2±112.9),AST(223.9±93.8),PT (132.9±152.6)s,APTT (131.4 ±153.9)s,染毒后48 h,TBIL和ALP值达到峰值[(TBIL(23.3±14.6)μmol/L,ALP (274.5 ±115.5) U/L],模型犬TBIL、TP和APTT在染毒后1周恢复至正常水平,ALT、AST和ALP在染毒后3周恢复至正常水平.染毒后24～72 h死亡3只,肝脏病理检查显示弥漫性肝细胞出血性坏死.染毒后24 h内,血浆中可检测到鹅膏肽类毒素;染毒后96h内,尿液中可检测到鹅膏肽类毒素.结论 鹅膏肽类毒素可引起肝细胞出血性坏死,导致急性肝功能衰竭,该模型符合含鹅膏肽类毒素蘑菇致中毒性肝功能衰竭临床病理生理特点,可应用于含鹅膏肽类毒素蘑菇中毒的诊断和治疗研究.     

低剂量微囊藻毒素对小鼠肝功能及氧化损伤的影响

目的:观察低剂量微囊藻毒素(MC-LR)染毒对小鼠血清及肝组织肝功能指标和氧化损伤指标的影响.方法:40只健康KM小鼠根据MC-LR的剂量分组,设0、0.25、0.5、1.0 μg/(kg·d)4个组,染毒10周,经腹腔注射染毒,测定血清和肝组织中ALT、AST、MDA、SOD、GSH-Px水平.结果:血清中:AST染毒组比对照组有显著升高,低、中剂量组升高,差异有统计学意义(P＜0.05);SOD活性随剂量增大呈增高趋势,高剂量组增高有统计学意义(P＜0.05),低、中剂量组无统计学意义(P＞0.05);GSH-Px活性在不同剂量组均有升高,中剂量组升高有统计学意义(P＜0.05).肝组织中:ALT、AST两项各染毒组与对照组比较均有升高趋势,中剂量组升高存在统计学意义(P＜0.05),SOD活性中剂量组增高有统计学意义(P＜0.05).结论:低MC-LR可以诱导小鼠肝功能损伤,但是染毒组抗氧化酶增高,对抗其氧化损伤作用.     

松花粉对砷中毒小鼠肝脏及血清一些生化指标的影响

目的 通过检测松花粉对砷中毒小鼠肝脏及血清一些生化指标的影响研究松花粉对砷中毒小鼠的恢复情况.方法 54只小鼠被随机分为3组:即A组(正常对照组),B组(治疗组),C组(NaAsO2对照组).正常对照组饮用蒸馏水;治疗组、NaAsO2对照组均隔天注射NaAsO2(500 μg/100g)进行砷染毒.治疗组,在砷染毒进行的第15 d后开始用松花粉灌胃(1 g/kg),至第45 d,取肝组织做病理分析,测血清丙氨酸氨基转移酶(ALT)、直接胆红素(DBLL)、尿酸(SUA).结果 NaAsO2中毒对照组与治疗组相比,肝炎症程度高;NaAsO2对照组与治疗组相比,ALT,SUA含量差异有统计学极显著性意义(P<0.01),DBLL差异有统计学显著性意义(P<0.05).结论 松花粉能降低砷中毒后小鼠肝肾的损伤程度.     

异甘草酸镁对大鼠百草枯中毒肺纤维化治疗作用的研究

目的 探讨异甘草酸镁(MgIG)对大鼠百草枯(paraquat,PQ)中毒所致肺纤维化的防治作用及可能的机制.方法 健康的SD雄性大鼠30只,随机分成5组:正常对照组、染毒对照组、MgIG低剂量(15 mg/kg)组、MgIG中剂量(30 mg/kg)组和MgIG高剂量(45 mg/kg)组;用20% PQ溶液按15 mg/kg行腹腔注射制作大鼠PQ中毒肺损伤模型,各治疗组于染毒后24 h按相应剂量MgIG行腹腔注射,正常对照组及染毒对照组注射生理盐水(按MgIG中剂量组的相应容量计算),直至死亡或被处死.于染毒后第14天全部处死,取肺组织行HE染色及Masson染色行病理学观察,并测定肺组织内羟脯氨酸(HYP)含量,同时取血清测定细胞间黏附因子-1(ICAM-1)及基质金属蛋白酶-9(MMP-9)含量.结果 所有大鼠均无自然死亡;光镜观察到染毒对照组静脉瘀血、淋巴增生、纤维母细胞增多,肺泡上皮增生明显,间质增厚.与染毒对照组相比,MgIG中剂量组的肺组织瘀血、水肿明显减轻,肺纤维化病理表现明显较轻,且肺内HYP明显下降(P均<0.01);血清中ICAM-1及MMP-9含量也明显降低(P<0.05或P<0.01).结论 MgIG中剂量对百草枯中毒大鼠肺组织纤维化损伤有一定的防治作用.     

硝酸镓对雌激素缺乏性骨质疏松大鼠胶原和骨钙蛋白的影响

背景:镓是一种人体内非必需微量元素.体内实验已证实,镓可直接抑制骨溶解,阻止骨钙释放,增加骨中钙含量,作为一种新的治疗代谢性骨病的药物,其抗骨转化机制尚不清楚.目的:观察硝酸镓对骨质疏松大鼠胶原和骨钙蛋白的影响.方法:雌性SD大鼠90只随机数字表法分为2组:对照组(n=20),显露双侧卵巢后缝合关闭腹腔;骨质疏松组(n=70),切除双侧卵巢建立骨质疏松大鼠模型.两组各随机取8只采集血、骨标本观察雌激素缺乏性骨质疏松模型复制情况.造模后骨质疏松组(n=62)随机数字表法分为4组:骨质疏松对照组(n=16)生理盐水腹腔注射,3次/周;低剂量镓盐组(n=16)腹腔注射硝酸镓,3次/周;高剂量镓盐组(n=15)按2 mg/kg腹腔注射硝酸镓,3次/周;雌激素组(n=15)腹腔注射雌二醇,3次/周.治疗12周后,检测骨标本中骨胶原、骨钙蛋白和羟脯氨酸水平.结果与结论:与对照组比较,骨质疏松对照组胶原含量降低(P<0.05),氨基己糖和羟脯氨酸含量升高(P<0.05),硫酸基差异无显著性意义.经镓盐及雌激素治疗后,胶原含量升高(P<0.05),氨基己糖和羟脯氨酸含量降低(P<0.05).高剂量镓盐组较低剂量镓盐组效果明显(P<0.05),与雌激素组效果相当(P>0.05).证实硝酸镓通过提高胶原含量,降低羟脯氨酸含量改善骨质疏松症骨代谢状态,2 mg/kg硝酸镓可取得类似雌激素治疗效果.     

灵孢多糖对α-鹅膏毒肽中毒小鼠肝肾的保护作用

目的:研究灵孢多糖对α-鹅膏毒肽中毒小鼠肝肾的影响并探索其对α-鹅膏毒肽中毒小鼠肝肾的影响是否存在量效关系。方法:将昆明雄性小鼠48只随机分为六组,即空白组、毒模组、灵孢多糖治疗1～4组,每组8只,复制α-鹅膏毒肽中毒模型4h后,空白组、毒模组腹腔注射生理盐水0.5mL,4个治疗组分别腹腔注射灵孢多糖0.5、1.0、2.0、4.0mL/kg,每天1次,连续3d。观察动物的行为表现及生存状况,实验72h小鼠摘眼球取血后对其进行解剖,计算肝肾脏器系数;检测ALT、AST、BUN、SCR;光镜下观察肝肾的病理组织改变。结果:与毒模组比较,灵孢多糖治疗组小鼠行为表现较好,肝肾脏器系数降低(P<0.05),ALT、AST、BUN、SCR较毒模组下降明显(P<0.05),肝肾病理损害程度减轻。结论:灵孢多糖对α-鹅膏毒肽中毒小鼠的肝肾具有保护作用,在本实验中灵孢多糖对α-鹅膏毒肽中毒小鼠的肝肾保护存在量效关系。     

甲泼尼龙联合环孢素A对百草枯中毒的防治

目的 在建立百草枯(paraquat,PQ)中毒致肺纤维化大鼠模型的基础上,探讨早期大剂量甲泼尼龙联合环孢素A治疗对PQ中毒大鼠肺组织病理变化、氧化一抗氧化指标和肺纤维化特异性指标的影响,以判断疗效.方法 (1)PQ中毒致肺纤维化大鼠模型的建立:40只雄性Wistar大鼠随机(随机数字法)分为5组,分别采用20 mg/kg,25 mg/kg,30 mg,/kg,35mg/kg和40 mg/kg5个PQ剂量水平进行染毒.计算各组大鼠的两周死亡率及观察肺组织病理形态学变化.以肺组织病理表现为纤维化、死亡率在可接受范围之内作为模型染毒剂量,并以生化指标验证.(2)甲泼尼龙联合环孢素A对PQ中毒大鼠肺纤维化的疗效观察:72只雄性Wistar大鼠随机分为正常对照组(8只)、模型组(16只)、药物干预组(48只)3组.正常对照组注射25 mg/kg生理盐水;其余组PQ 25 mg/kg染毒.药物干预组再随机分为3组(每组16只),分别于染毒后2 h,24 h,72 h三个时间点单次应用甲泼尼龙(90 mg/kg)联合环孢素A(22.5 mg/kg).染毒后7 d,14 d观察大鼠肺组织病理变化,采用碱水解法、黄嘌呤氧化酶法和硫代巴比妥酸法分别测定肺组织超氧化物歧化酶(SOD)、丙二醛(MDA)和羟脯氨酸(HPY)的含量.组间比较采用两因素析因设计的方差分析,组内比较采用单因素3水平设计的方差分析.结果 25 mg/kg为肺纤维化大鼠模型的PQ染毒剂量.与模型组比较,各药物干预组大鼠肺组织肺泡数量明显增多,成纤维细胞增生程度较轻,胶原及纤维含量较少.与模型组比较,各药物干预组大鼠肺组织SOD含最增加,HPY和NDA含量明显降低(P＜0.05或P＜0.01).与72 h药物干预组比较,2 h,24 h药物干预组大鼠肺组织成纤维细胞增生程度较轻,胶原、纤维较少,肺组织SOD含量明显升高(P＜0.05或P＜0.01),MDA含量明显降低(P＜0.01).结论 早期联合应用大剂量甲泼尼龙和环孢素A治疗PQ中毒大鼠,可以显著减轻PQ中毒所致的肺组织氧化损伤和肺纤维化程度,改善预后.     

健胃愈疡颗粒干预下大鼠胃溃疡黏膜乳癌相关肽和血小板活化因子的表达及与胃黏膜疏水性的相关性研究

目的:观察对胃溃疡复发有较好疗效的健胃愈疡颗粒对溃疡黏膜乳腺癌相关肽和血小板活化因子表达的影响,分析其可能的作用机制。方法:实验于2005-07/2006-07在湘雅医院中心实验室完成。SD大鼠110只,雌雄各半,随机抽签法分为5组,即正常对照组、假手术组、雷尼替丁组、健胃愈疡组,各20只;模型组30只。以Okabe改良法复制大鼠实验性胃溃疡,假手术组仅以生理盐水代替乙酸注入玻管内。造模后24h,雷尼替丁组、健胃愈疡组大鼠分别灌服盐酸雷尼替丁和健胃愈疡颗粒(药物组成为:柴胡、党参、白芍、延胡索、白芨、珍珠层粉、青黛、甘草,湖南湘雅制药有限公司生产)药液10mL/kg,分别相当于2.70,1.62g/kg,1次/d。假手术组、模型组灌服蒸馏水10mL/kg。10d后各组中随机取出10只大鼠剖腹取胃(处死前大鼠禁食24h),90d时将模型组20只大鼠再分为模型复发组和模型非复发组,各10只;除正常对照组、假手术组、模型非复发组大鼠腹腔内注射生理盐水外,其余各组大鼠腹腔内注射白细胞介素1,1μg/kg;在注射48h,大鼠禁食24h后,剖腹取胃。观察其对胃溃疡大鼠胃黏膜氨基己糖及磷脂含量、溃疡指数和胃黏膜血流的影响,并用RT-PCR观察乳癌相关肽乳癌相关肽和血小板活化因子表达的变化。结果:实验动物110只,全部进入结果分析。①模型组10,92d胃黏膜血流均低于正常对照组(P<0.01);健胃愈疡组同期胃黏膜血流均高于模型组(P<0.01)。②健胃愈疡组和雷尼替丁组10d溃疡指数均低于模型组(P<0.01,P<0.05);模型复发组、健胃愈疡组和雷尼替丁组92d溃疡指数均高于模型组(P<0.01);健胃愈疡组10,92d溃疡指数及复发率均低于雷尼替丁组(P<0.05,P<0.01)。③模型组10,92d氨基己糖和磷脂含量均低于正常对照组(P<0.01)。健胃愈疡组10,92d氨基己糖和磷脂含量均高于模型组和雷尼替丁组(P<0.01)。溃疡指数与氨基已糖、磷脂含量呈负相关(r=-0.957,-0.960,P<0.01)。④健胃愈疡组和雷尼替丁组10d乳癌相关肽mRNA表达较正常组和假手术组提高,血小板活化因子mRNA的表达下调(P<0.01),健胃愈疡组两指标表达变化较雷尼替丁组显著(P<0.01);模型复发组、健胃愈疡组和雷尼替丁组92d乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异无显著性意义(P>0.05);模型组乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异有显著性意义(P<0.01)。结论:健胃愈疡颗粒可提高乳癌相关肽mRNA及下调血小板活化因子mRNA的表达,影响胃黏膜氨基己糖及磷脂含量,可能是其促进溃疡愈合的机制之一。     

肺纤维化大鼠血清克拉拉细胞蛋白和表面活性蛋白-D动态变化及早期诊断意义

目的 探讨克拉拉细胞蛋白(CC16)和表面活性蛋白-D(SP-D)在肺纤维化大鼠中的表达水平及早期诊断意义.方法 Wistar大鼠60只随机分为正常对照组(对照组)、博莱霉素致肺纤维化组(模型组).每组30只,分别于造模后1、3、7、14、28 d处死,采用HE、Masson染色观察其肺组织病理变化,碱水解法测定肺组织羟脯氨酸含量,酶联免疫吸附法测定血清CC16、SP-D水平.结果 模型组大鼠肺组织羟脯氨酸含量自第7天[(913.1±69.3)μg/g]起,较对照组[(790.5±36.8)μg/g]升高(P<0.05);血清CC16自第3天[(27.34±0.32)μg/L]开始,低于对照组[(27.85 ±0.32)μg/L](P<0.05),并随病情进展而逐渐降低;血清SP-D各时相均高于对照组(P均<0.05),并且随病情进展而逐渐升高.结论 血清CC16、SP-D在大鼠肺纤维化早期有明显改变,其水平变化可能为肺纤维化的早期诊断提供生物学指标.     

气体信号分子硫化氢在热性惊厥脑损伤形成机制中的作用

目的:探讨硫化氢(H2S)对反复热性惊厥(febrile seizures,FS)脑损伤的影响。方法:大鼠随机分为对照组、FS组、FS+NaHS组、FS+HA(hydroxylamine)组。采用热水浴诱导大鼠FS,隔日诱导1次,共10次。记录大鼠惊厥潜伏期、持续时间及强度;分光光度计法测定大鼠血浆中H~2|S含量;电镜观察海马神经元超微结构的改变;Timm染色观察海马发芽情况;原位杂交和免疫组化分别观察c-fos基因和Fos蛋白表达情况。结果:FS+NaHS组和FS+HA组大鼠惊厥潜伏期、持续时间及强度的改变与FS组相比无明显差异;FS+NaHS组大鼠海马神经元超微结构损伤性改变较FS组明显减轻,而FS+HA组则明显加重;NaHS干预后海马苔藓纤维发芽减轻,而HA干预后海马发芽加重;NaHS的干预使c-fos基因和Fos蛋白表达降低,而HA的干预使其表达增强。结论:应用H~2|S外源性供体NaHS和胱硫醚-β-合成酶抑制剂HA的干预研究表明,气体信号分子硫化氢参与了热性惊厥脑损伤的发生与发展过程。     

Effects of barbiturate administration on hepatic and renal biochemical parameters in new zealand white rabbits.

To assess the initial response of various plasma hepatic and renal biochemical parameters to barbiturates, we assigned 30 new Zealand White rabbits to three treatment groups (n = 10 each): control (saline solution injected intravenously), pentobarbitone (30 mg/kg intravenously), and thiopentone (20 mg/kg intravenously). Blood samples were obtained from the central ear artery at six time points: before injection injection of the anesthetics or saline and at 10, 30, 60, and 120 min and 24 h afterward. Plasma alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamiltransferase, blood urea nitrogen, and creatinine levels were measured using an autoanalyzer, and those of the treatment groups were compared with control group levels. The administration of thiopentone significantly increased plasma levels of alanine aminotransferase, aspartate aminotransferase, gamma glutamiltransferase and blood urea nitrogen, but that of plasma alkaline phosphatase significantly decreased. Plasma alkaline phosphatase and gamma glutamiltransferase levels significantly increased after pentobarbitone administration. From these results, we concluded that plasma levels of some hepatic and renal enzyme concentrations increase significantly within a short time after administration of thiopentone or pentobarbitone. Therefore, caution is required in interpreting data on plasma biochemical parameters from rabbits anesthetized with pentobarbitone or thiopentone.     

脑电双频指数监测下不同剂量舒芬太尼麻醉诱导对老年高血压患者气管插管反应的影响

目的探讨脑电双频指数（BIS）监测下不同剂量舒芬太尼静脉麻醉诱导对气管插管反应的影响。方法选择择期行全麻手术的老年高血压患者60例,年龄65~85岁,ASAI~Ⅱ级,按不同剂量舒芬太尼随机分为3组,每组20例。Ⅰ组给予舒芬太尼0.2μg/kg,Ⅱ组0.3μg/kg,Ⅲ组0.4μg/kg,在BIS监测下注射丙泊酚2mg/kg和顺式阿曲库铵0.15mg/kg,经口气管插管。记录麻醉诱导前（t0）、诱导给药后（t1）、插管时（t2）、插管后1min（t3）、插管后3min（t4）、插管后5min（t5）的收缩压（SBP）、舒张压（DBP）、心率（HR）及BIS的变化。结果与诱导前相比,给药后3组SBP、DBP、HR及BIS均显著下降（P〈0.05）,以Ⅲ组下降较明显（P〈0.05）;插管时SBP、DBP、HR及BIS均上升,Ⅰ组升高较明显（P〈0.05）,Ⅱ、Ⅲ组升高差异无统计学意义（P〉0.05）;BIS组间比较差异有统计学意义（P〈0.05）,但3组插管后BIS均小于55。结论在老年高血压患者中,0.3μg/kg舒芬太尼麻醉诱导能有效地抑制气管插管应激反应,插管期间血流动力学平稳,是临床使用的最佳剂量。     

Treatment with either COX‐2 inhibitor or 5‐LOX inhibitor causes no compensation between COX‐2 pathway and 5‐LOX pathway in chronic aluminum overload‐induced liver injury in rats

This study was designed to observe the compensation between cyclooxygenase‐2 pathway and 5‐lipoxygenase pathway in chronic aluminum overload‐induced liver injury rats. A rat hepatic injury model of chronic aluminum injury was established by the intragastric administration of aluminum gluconate (Al3 + 200 mg/kg per day, 5 days a week for 20 weeks). The COX‐2 inhibitor [meloxicam (1 mg/kg)] and 5‐LOX inhibitor [caffeic acid (30 mg/kg)] were intragastrically administered 1 h after aluminum administration. The histopathology was detected by hematoxylin‐eosin staining. A series of biochemical indicators were measured with biochemistry assay or ELISAs. The expressions of COX‐2 and 5‐LOX were measured by immunohistochemistry. Our experimental results showed that aluminum overload caused a significant damage to the liver and also significantly increased the expressions of COX‐2, 5‐LOX and the levels of inflammation and oxidative stress. The administration of meloxicam and caffeic acid significantly protected livers against histopathological injury, significantly decreased plasma ALT, AST, and ALP levels, significantly decreased TNF‐α, IL‐6, IL‐1β levels, and oxidative stress. However, the administration of caffeic acid did not significantly increase the expression of COX‐2 compared with the model group. On the other hand, the administration of meloxicam also did not significantly increase the expression of 5‐LOX compared with the model group. Our results indicate that there is no compensation between COX‐2 pathway and 5‐LOX pathway by inhibiting either COX‐2 or 5‐LOX in chronic aluminum overload‐induced liver injury rat.     

灯盏花素减轻顺铂对大鼠肾损害及肾细胞凋亡机制的研究

目的探讨应用灯盏花素减轻顺铂对大鼠肾损害及肾细胞凋亡的作用机制。方法48只SD大鼠分为对照组、模型组、25mg／kg灯盏花素组（灯盏花素1组）和50mg／kg灯盏花素组（灯盏花素2组）各12只。对照组给予羧甲基纤维素钠溶液灌胃,模型组、灯盏花素1组和2组均腹腔注射顺铂8mg／kg造模。灯盏花素1组和2组分别以25mg／kg和50mg／kg灯盏花素灌胃,给药7d后计算4组肾脏指数,采用原位缺15末端标记法检测肾细胞凋亡情况,左肾采用蛋白质印迹法检测肾皮质Bax、Bcl-2表达水平,右肾采用免疫组织化学法检测肾组织凋亡蛋白Bax和Bcl-2表达水平。结果模型组、灯盏花素1组和2组肾脏指数、凋亡指数及Bax、Bcl-2表达水平高于对照组（P〈0．05）;灯盏花素2组肾脏指数、凋亡指数、Bax表达水平及Bax／Bcl-2比值低于模型组、Bcl-2表达水平高于模型组（P〈0．05）;灯盏花素1组肾脏指数和凋亡指数高于2组（P〈0．05）。结论灯盏花素可增强凋亡蛋白Bcl-2表达、降低Bax表达,影响线粒体凋亡通路,从而减轻顺铂对肾损害大鼠肾细胞的凋亡。     

Effects of a potent peroxynitrite decomposition catalyst in murine models of endotoxemia and sepsis

Excessive free-radical production due to various bacterial components released during bacterial infection has been linked to cell death and tissue injury. Peroxynitrite is a highly reactive oxidant produced by the combination of nitric oxide (NO) and superoxide anion, which has been implicated in cell death and tissue injury in various forms of critical illness. Pharmacological decomposition of peroxynitrite may represent a potential therapeutic approach in diseases associated with the overproduction of NO and superoxide. In the present study, we tested the effect of a potent peroxynitrite decomposition catalyst in murine models of endotoxemia and sepsis. Mice were injected i.p. with LPS 40 mg/kg with or without FP15 [Fe(III) tetrakis-2-(N-triethylene glycol monomethyl ether)pyridyl porphyrin] (0.1, 0.3, 1, 3, or 10 mg/kg per hour). Mice were killed 12 h later, followed by the harvesting of samples from the lung, liver, and gut for malondialdehyde and myeloperoxidase measurements. In other subsets of animals, blood samples were obtained by cardiac puncture at 1.5, 4, and 8 h after LPS administration for cytokine (TNF-α, IL-1β, and IL-10), nitrite/nitrate, alanine aminotransferase, and blood urea nitrogen measurements. Endotoxemic animals showed an increase in survival from 25% to 80% at the FP15 doses of 0.3 and 1 mg/kg per hour. The same dose of FP15 had no effect on plasma levels of nitrite/nitrate. There was a reduction in liver and lung malondialdehyde in the endotoxemic animals pretreated with FP15, as well as in hepatic myeloperoxidase and biochemical markers of liver and kidney damage (alanine aminotransferase and blood urea nitrogen). In a bacterial model of sepsis induced by cecal ligation and puncture, FP15 treatment (0.3 mg/kg per day) significantly protected against mortality. The current data support the view that peroxynitrite is a critical factor mediating liver, gut, and lung injury in endotoxemia and septic shock: its pharmacological neutralization may be of therapeutic benefit.     

探讨不同浓度刀豆蛋白A对小鼠肝损伤的影响

目的探讨刀豆蛋白A(ConA)诱导小鼠急性肝损伤,形成肝纤维化的最佳成模时间与剂量。方法将BALb/c小鼠60只随机分为6组,即正常对照组和模型A、B、C、D、E组,每组10只。除正常对照组外,模型组分别经尾静脉注射8、10、12、14、16mg/kgConA。每周1次检测各组小鼠血清丙氨酸氨基转移酶(ALT)、总胆汁酸酶(TBA)、透明质酸酶(HA)水平,持续检测8周。8周后检测肝组织匀浆中丙二醛(MDA)、超氧化物歧化酶(SOD)、一氧化氮(NO)水平。结果经不同剂量ConA诱导后随注射次数增多和持续时间延长,小鼠血清ALT、TBA、HA和肝组织匀浆中MDA、NO、SOD水平与正常对照组比较,差异有统计学意义(P<0.05)。结论小鼠经尾静脉注射剂量为12mg/kgConA第5周可获取理想的肝纤维化动物模型。     

四氯化碳和醋氨酚急性肝损伤犬模型的比较

摘 要 目的：研究比较四氯化碳（CCl4）和醋氨酚（APAP）所致急性肝损伤犬模型的异同，为药物性肝炎的相关研究提供动物模型选择的实验依据。方法：24只健康杂种犬随机分为CCl4组和APAP 组（n=12）。CCl4组一次性腹腔注射50.0%（W/W）CCl4花生油溶液，0.9ml/kg体重。APAP组三次多点皮下注射600ｇ/Ｌ APAP溶液，首次剂量为750mg/kg体重，于首次注射后9ｈ和24ｈ分别再次注射，剂量为200mg/kg体重。分别观察各犬的全身情况、记录生存时间，测定血液生化指标，包括丙氨酸氨基转移酶（ALT）、丙氨酸氨基转移酶与天门冬氨酸氨基转移酶比值（AST/ALT）、血清总胆红素（TBIL）、凝血酶原时间（PT）、血氨（AMMO）、尿素氮（BUN），犬死亡时或存活15d时取肝脏组织行病理检查。结果：二组生存率比较差异无显著性意义（P>0.05）。二组血液生化指标3天内达高峰；CCl4对肝功能的影响比APAP明显（P<0.05），而APAP肾毒性较CCl4大（P<0.05）；肝炎表现CCl4组较重。肝脏病理改变CCl4较显著。肝外表现CCl4注射后迅速出现消化道和神经症状改变，其精神、饮食变化较APAP模型犬显著。结论：CCl4对犬的生存状态影响和肝脏的损害程度均高于APAP，而APAP的肾毒性较CCl4显著。     

小鼠肝窦内皮细胞损伤在肝静脉闭塞病中的作用研究

本研究探讨野百合碱诱导的小鼠肝窦内皮细胞损伤在肝静脉闭塞病中的作用。将BALB/c小鼠随机分为2组,即生理盐水组(n=15)和野百合碱组(n=15),分别按10 ml/kg和200 mg/kg灌胃,连续3 d。灌胃后第3、4、6、8和10天检测各组小鼠肝功能(总胆红素、丙氨酸转氨酶、碱性磷酸酶)、肝脏指数及活化血小板比例;HE染色、Masson染色及免疫组织化学染色观察肝细胞及肝窦内皮细胞的损伤情况、肝脏纤维化程度等;电子显微镜观察肝窦内皮细胞损伤、炎细胞浸润及血小板聚集情况。结果显示,野百合碱组与生理盐水组相比在光学显微镜和电子显微镜下均可见肝窦内皮细胞损伤、大量血小板黏附和聚集、中央静脉和肝血窦纤维化;与生理盐水组相比,野百合碱组外周血活化血小板比例升高(P<0.05),肝脏指数升高(P<0.05),肝功能异常并有腹水形成。结论:野百合碱诱导的肝窦内皮细胞损伤是肝静脉闭塞病的始动因素,且该肝窦内皮细胞损伤可能具有自限性,但纤维化持续存在。     

Peroxynitrite is a critical mediator of acetaminophen hepatotoxicity in murine livers: protection by glutathione

Acetaminophen (AAP) overdose causes formation of nitrotyrosine, a footprint of peroxynitrite, in centrilobular hepatocytes. The importance of peroxynitrite for the pathophysiology, however, is unclear. C3Heb/FeJ mice were treated with 300 mg/kg AAP. To accelerate the restoration of hepatic glutathione (GSH) levels as potential endogenous scavengers of peroxynitrite, some groups of animals received 200 mg of GSH/kg i.v. at different time points after AAP. AAP induced severe liver cell damage at 6 h. Total liver and mitochondrial glutathione levels decreased by >90% at 1 h but recovered to 75 and 45%, respectively, of untreated values at 6 h after AAP. In addition, the hepatic and mitochondrial glutathione disulfide (GSSG) content was significantly increased over baseline, suggesting a mitochondrial oxidant stress. Moreover, centrilobular hepatocytes stained for nitrotyrosine. Treatment with GSH at t = 0 restored hepatic GSH levels and completely prevented the mitochondrial oxidant stress, peroxynitrite formation, and liver cell injury. In contrast, treatment at 1.5 and 2.25 h restored hepatic and mitochondrial GSH levels but did not prevent the increase in GSSG formation. Nitrotyrosine adduct formation and liver injury, however, was substantially reduced. GSH treatment at 3 h after AAP was ineffective. Similar results were obtained when these experiments were repeated with glutathione peroxidase-deficient animals. Our data suggest that early GSH treatment (t = 0) prevented cell injury by improving the detoxification of the reactive metabolite of AAP. Delayed GSH treatment enhanced hepatic GSH levels, which scavenged peroxynitrite in a spontaneous reaction. Thus, peroxynitrite is an important mediator of AAP-induced liver cell necrosis.