丙酮酸乙酯对烫伤大鼠肝组织高迁移率族蛋白B1表达和肝功能的影响

目的探讨烫伤大鼠肝组织高迁移率族蛋白B1(HMGB1)表达的变化规律,观察丙酮酸乙酯(EP)对烫伤后肝组织HMGB1表达及肝功能的影响。方法采用大鼠30%总体表面积Ⅲ度烫伤模型,78只雄性Wistar大鼠随机分为假伤组(n=18)、烫伤组(n=30,烫伤后2h腹腔给予林格液3ml)、丙酮酸乙酯(EP)治疗组(n=30,烫伤后2h腹腔给予EP3ml)。3组动物分别于伤后第8、24、72h时点活杀,留取肝组织检测其HMGB1基因/蛋白表达,留取血标本检测肝功能指标。采用逆转录聚合酶链反应及蛋白免疫印记法检测肝组织HMGB1基因/蛋白表达,应用全自动生化分析仪测定血清天冬氨酸转氨酶(AST)和丙氨酸转氨酶(ALT)水平。结果与假伤组比较,严重烫伤组大鼠肝组织HMGB1 mRNA表达及蛋白水平均显著增高(P<0.05或P<0.01),同时血清AST和ALT水平亦显著升高(P<0.05或P<0.01)。EP治疗组大鼠肝组织HMGB1表达显著下调,血清AST和ALT水平不同程度地明显下降(P<0.01或P<0.05)。结论HMGB1参与了烫伤大鼠的炎症反应过程,应用EP治疗可有效抑制烫伤后肝组织HMGB1的表达,并显著减轻烫伤延迟复苏所致肝功能障碍。     

JAK/STAT通路对烫伤脓毒症大鼠Toll样受体基因表达的调节作用

目的：探讨Janus激酶／信号转导和转录激活子（JAK／STAT）通路在烫伤脓毒症大鼠Toll样受体2（TLR2）基因表达调控中的意义。方法：Wistar大鼠38只随机分为正常对照组（n=6)、烫伤后金黄色葡萄球菌（金葡菌）感染组（n=12)、AG490拮抗组（n=20)和雷帕霉素（Rapamycin,RPM)拮抗组（n=10), 检测动物肝、肾、肺组织中TLR2和肿瘤坏死因子－α（TNF－α）基因表达的改变。结果：烫伤合并金葡菌攻击后0．5h和2h，动物肝、肾、肺组织中TLR2 mRNA表达显著增高（P＜0．05或P＜0．01）。RPM干预可有效抑制动脉肝、肾组织TLR2 mRNA表达，但对肺脏TLR2 mRNA表达无明显影响；而AG490拮抗组动物各组织中TLR2 mRNA表达与未干预组相比均无明显差异。烫伤合并金葡菌感染后2h大鼠肝、肺、肾组织TNF－α基因表达均显著升高（P均＜0．01）。给予RPM可明显抑制各组织中TNF－α mRNA表达（P＜0．05或P＜0．01），AG490拮抗组大鼠肝、肾组织中TNF－α表达亦均显著低于未拮抗组（P均＜0．01）。结论：烫伤后金葡菌感染可促进体内TLR2基因表达，STAT可能直接或通过其诱生的炎症介质参与了对TLR2 mRNA表达的调控。     

抑制JAK/STAT通路对烫伤后金黄色葡萄球菌脓毒症大鼠肝损害的影响

目的：研究JAK激酶／信号转导和转录激活子（JAK／STAT）通路对烫伤后金黄色葡萄球菌（金葡菌）感染致严重脓毒症大鼠肝损害的影响。方法：采用烫伤后金葡菌感染致严重脓毒症的大鼠模型,60只动物随机分为正常对照组,烫伤对照组,烫伤后金葡菌感染组,JAK2激酶抑制剂AG490和STAT3抑制剂雷帕霉素（RPM）处理组,采用逆转录多聚酶链式反应和酶联免疫吸附法,分别检测肝组织中肿瘤坏死因子－α（TNF－α）基因和蛋白表达,肝功能指标的改变。结果：AG490和RPM早期干预均能显著降低烫伤脓毒症大鼠肝组织TNF－αmRNA表达峰值（P均＜0．01）,AG490处理后2小时肝组织TNF－α的蛋白水平也有所下降,同时,血清丙氨酸转氨酶,天冬氨酸转氨酶亦显著降低（P＜0．01或P＜0．05）,结论：脓毒症早期抑制JAK／STAT通路的活化有助于减轻肝组织炎症反应及急性肝损害。     

还原型谷胱甘肽对脓毒症大鼠肝损伤时肝组织热休克蛋白70的影响

目的 通过观察还原型谷胱甘肽(GSH)对脓毒症大鼠急性肝损伤时肝组织热休克蛋白70(HSP70)和肿瘤坏死因子-α(TNF-α)水平的影响,探讨GSH对脓毒症大鼠急性肝损伤的保护作用及其可能的机制.方法采用盲肠结扎穿孔术(CLP)制备SD大鼠脓毒症肝损伤模型.实验大鼠随机分成假手术组、模型组、GSH干预组(每组各24只),每组大鼠再随机分为0、2、6、24 h 4个亚组(每组各6只).GSH干预组在造模后立即经尾静脉给予GSH 300 mg/kg(0.1 mL),假手术组和模型组则给予等量生理盐水.每组大鼠在CLP术后0、2、6、24 h分别采集血标本和肝组织标本.HE染色观察肝组织病理改变;检测血清肝功能和肝组织HSP70和TNF-α水平的变化.结果与假手术组相比,模型组大鼠血清肝功能(TBIL、ALT和AST)水平在术后6 h起开始升高,术后24 h仍持续升高;肝组织HSP70水平在术后2 h即显著升高,术后6 h达到高峰,术后24 h则有所回落;肝组织TNF-α水平在术后2 h起开始升高,术后6 h达到高峰,术后24 h有所回落;术后24 h肝组织HE染色显示肝细胞肿胀、大量炎性细胞浸润、细胞变性等损伤性改变.与模型组相比,GSH干预组在术后6 h和24 h血清肝功能损伤指标及肝组织TNF-α水平显著降低(P<0.05),而肝组织HSP70水平在术后2 h、6 h和24 h均显著升高(P<0.05);术后24 h肝组织的病理学损伤性改变明显减轻.结论在脓毒症早期应用GSH治疗对脓毒症急性肝损伤有保护作用;其作用机制可能是通过提高肝组织HSP70浓度,降低肝组织TNF-α浓度,从而减轻炎性因子对肝组织的损伤.     

腹腔感染性脓毒症可溶性髓样细胞触发受体(sTREM-1)与Janus激酶-信号转导和转录激活因子(JAK/STAT)通路的关系

目的 通过动物脓毒症模型探讨可溶性髓样细胞触发受体(sTREM-1)与Janus激酶-信号转导和转录激活因子(JAK/STAT)通路的关系.方法 采用盲肠结扎穿孔(CLP)法制作大鼠脓毒症模型,大鼠随机(随机数字法)分为正常对照组(n=6)、假手术组(n=24)、CLP组(n=48)、JAK 2抑制剂(AG 490)组(n=48)和STAT3抑制剂(雷帕霉素,RPM)组(n=48).留取外周血行流式细胞仪分析CD4+ CD25+ Treg细胞/CD4+T细胞比值.采用逆转录多聚酶链式反应(RT-PCR)测定肝组织sTREM-1 mRNA表达水平.结果 CLP后6h肝sTREM-1 mRNA表达即高于对照组和假手术组,且随时间变化逐渐升高.AG490组肝组织sTREM-1 mRNA的表达在术后6h、24 h(1.572±0.051,2.063±0.025)较同时间点CLP组(1.592±0.036,2.082±0.021)差异无统计学意义(P＜0.05),而在48 h和72 h AG490组肝组织sTREM-1 mRNA的表达(2.522±0.083,3.153±0.021)低于同时间点CLP组(2.592±0.055,3.204±0.013) (P＜0.05).术后6 h RPM组肝组织sTREM-1mRNA的表达(1.581±0.017)较CLP组差异无统计学意义(P＜0.05),而在术后24、48、72 h RPM组肝组织sTREM-1 mRNA的表达(1.486±0.019,1.263±0.011,1.115±0.022)显著低于同时间点CLP组肝组织sTREM-1 mRNA的表达(P＜0.05).结论 sTREM-1因子与JAK/STAT通路有关,阻断JAK/STAT通路能够抑制sTREM-1 mRNA的表达,减缓脓毒症炎症反应的进展.     

还原型谷胱甘肽对脓毒症大鼠心肌组织中Toll样受体4表达的影响

目的:探讨还原型谷胱甘肽(glutathione,GSH)对脓毒症大鼠急性心肌损伤的保护作用及其机制。方法:采用盲肠结扎穿孔术(cecal ligation and puncture,CLP)建立SD大鼠脓毒症致急性心肌损伤模型。按照随机数字表将大鼠随机分为正常组(n=6)、假手术组(n=18)、脓毒症组(n=18)、GSH干预组(n=18)。GSH干预组于CLP术后经尾静脉注射GSH60 mg/kg,共0.1 mL;假手术组和脓毒症组则给予等量0.9%氯化钠溶液。除正常组外,每组大鼠再按术后6 h、12 h、24 h分为3个亚组(每组各6只),各亚组组大鼠在CLP术后相应时间点采集血清及心肌组织标本。所有大鼠均于血标本采集完毕后处死。HE染色观察心肌组织病理改变;采用自动生化分析仪检测血清肌酸激酶同工酶(creatine kinase MB isoenzyme,CK-MB)的水平,采用实时荧光定量逆转录–聚合酶链反应法检测心肌组织Toll样受体4(Toll-like receptor 4,TLR4)的mRNA表达。结果:与假手术组及正常组比较,脓毒症组大鼠术后6 h血清CK-MB水平和心肌组织TLR4 mRNA表达开始升高,12 h达到高峰,24 h仍明显升高,差异有统计学意义(P0.05),且术后24 h心肌组织HE染色显示肌纤维结构排列疏松紊乱,间质充血水肿,见大量炎性反应细胞浸润等损伤性改变;与脓毒症组比较,GSH干预组大鼠术后6 h血清CK-MB水平和心肌组织TLR4 mRNA表达已有所下降,术后12 h、24 h明显下降,差异均有统计学意义(P0.05),且术后24 h时心肌组织上述病理学损伤性改变也明显减轻。结论:心肌组织TLR4 mRNA的高表达在脓毒症致急性心肌损伤中起着重要的作用,而在脓毒症早期应用GSH干预可抑制心肌组织TLR4 mRNA的表达,对脓毒症致急性心肌损伤有保护作用。     

脓毒症大鼠肝脏Toll样受体4水平及还原型谷胱甘肽的干预研究

目的：观察脓毒症大鼠急性肝损伤时肝脏Toll样受体4（TLR4）和肿瘤坏死因子α（TNF-α）水平的变化,探讨还原型谷胱甘肽（GSH）对脓毒症大鼠急性肝损伤的保护作用及其机制。方法：采用盲肠结扎穿孔术（CLP）制备SD大鼠脓毒症肝损伤模型。实验大鼠随机分成假手术组、模型组、GSH干预组（每组各24只）,每组大鼠再按按0h、2h、6h、24h分为4个亚组（每组各6只）。GSH干预组在造模后立即经尾静脉给予GSH（300mg.kg-1）共0.1mL,假手术组和模型组则给予等量0.9%氯化钠溶液。每组大鼠在4个时间点（CLP术后0h、2h、6h、24h）采集血标本和肝组织标本。HE染色观察肝组织病理改变;检测血清肝功能和肝组织TLR4和TNF-α水平的变化。结果：与假手术组相比,模型组大鼠血清肝功能水平在术后6h起开始升高,术后24h仍持续升高;肝组织TLR4和TNF-α水平均在术后2h显著升高,术后6h达到高峰,术后24h有所回落;术后24h肝组织HE染色显示肝细胞肿胀、大量炎性细胞浸润、细胞变性等损伤性改变。与模型组相比,GSH干预组在术后6h和24h血清肝功能损伤指标显著降低（P〈0.05）,而肝组织TLR4和TNF-α水平在术后2h、6h、24h均显著降低（P〈0.05）,肝组织的病理学损伤性改变也明显减轻。结论：在脓毒症早期肝组织TLR4及其调控的炎性因子TNF-α水平增高在脓毒症急性肝损伤中起重要作用;脓毒症早期应用GSH治疗可能通过降低TLR4水平,减少肝组织TNF-α浓度,对脓毒症急性肝损伤有保护作用。     

杀菌-通透性增加蛋白对脓毒症大鼠肝组织致炎与抗炎细胞因子表达的影响

目的：探讨杀菌－通透性增加蛋白（BPI）对脓毒症大鼠肝组织致炎与抗炎细胞因子表达的影响。方法：采用大鼠盲肠结扎穿孔（CLP）致脓毒症模型,动物随机分为正常对照组、脓毒症组和BPI治疗组。分别于CLP后12和24小时处死动物,检测肝组织肿瘤坏死因子－α（TNF－α）、白介素－10（IL－10）mRNA及其蛋白表达以及肝功能指标的改变。结果：脓毒症动物肝组织TNF－α及IL－10基因和蛋白表达均显著升高（P＜0．05或P＜0．01）,其中CLP后12小时组织TNF－α蛋白水平升高幅度明显大于IL－10的改变。BPI治疗12小时组TNF－α基因及蛋白均显著下降（P＜0．05或P＜0．01）,而IL－10则不同程度地升高;同时,治疗组12小时肝功能指标亦明显改善。结论：脓毒症早期应用BPI治疗可明显抑制肝组织TNF－α等致炎细胞因子表达,并上调局部组织IL－10等抗炎细胞因子的产生,从而有助于恢复体内炎症反应平衡与减轻脓毒症所致肝损伤。     

血必净对创伤弧菌脓毒症大鼠肺组织核因子-κB p65表达作用的研究

目的 观察创伤弧菌脓毒症大鼠肺组织核因子-κB(NF-κB)p65基因及蛋白表达,并探讨血必净对其的干预作用.方法 SD大鼠110只,随机分为正常组(A组,n＝10)、创伤弧菌脓毒症组(B组,n＝50,采用大鼠左下肢皮下注射创伤弧菌悬液制作大鼠创伤弧菌脓毒症模型)和血必净治疗干预组(C组,n＝50,感染后半小时腹腔注射血必净4 mL/kg).B、C组于染菌后1、6、12、24、48 h活杀(各时间点n=10),采用逆转录-聚合酶链式反应(RT-PCR) 法、Western blot法和双抗体夹心酶联免疫吸附法(ELISA)分别检测大鼠肺组织NF-κB p65的基因与蛋白表达及IL-10的含量,数据采用单因素方差分析.结果 与A组比较,B组大鼠肺组织创伤弧菌感染后6、12 h NF-κB p65 mRNA表达量与6、12、24和48 h肺组织NF-κB p65蛋白表达量均明显增高 (P<0.05);与B组相同时间点比较,C组6 h肺组织NF-κB p65 mRNA表达量与12、24及48 h肺组织NF-κB p65 蛋白表达量明显减少(P<0.05); 与A组比较,B组创伤弧菌菌感染12、24和48 h IL-10的含量明显增加(P<0.05),与B组相同时间点比较,C组24 h(52.444±9.605)肺组织IL-10的含量明显增高(P<0.05);感染后48 h,大鼠肺内血管明显充血,间质水肿并伴炎性浸润,肺泡腔塌陷,血必净干预后,肺组织损伤有所减轻.结论 NF-κB参与了创伤弧菌脓毒症肺损伤过程;血必净能抑制NF-κB p65的表达,从而起到保护创伤弧菌脓毒症大鼠肺组织的作用.     

抑制枯否细胞对脓毒症大鼠肝脏微循环的影响

目的 探讨抑制枯否细胞(Kupffer cells,KCs)对脓毒症大鼠肝脏微循环的影响.方法 采用盲肠结扎穿孔法(CLP)制备大鼠脓毒症急性肝损伤模型.造模前1 d和2 d经尾静脉注射三氯化钆(GdC13)去除KCs.将60只健康SD大鼠随机分为四组,即对照组、假手术组(Sham组)、模型组(CLP组)和GdC13组(CLP+GdC13组).各组动物于术后24 h处死.检测血中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、内毒素(ET)、内皮素-1(ET-1)及一氧化氮(NO)的水平.提取肝组织RNA,采用RT-PCR方法检测ET-1、eNOS、iNOS及HO-1 mRNA的表达.结果 与对照组比较,脓毒症大鼠血中ALT、AST、ET、ET-1及NO水平显著升高(P<0.05);去除KCs后,脓毒症大鼠血中ALT、AST、ET、ET-1及NO水平显著降低(P<0.05).脓毒症大鼠肝组织ET-1、eNOS、iNOS及HO-1 mRNA 表达水平较对照组显著升高(P<0.05);去除KCs后,肝组织中iNOS及HO-1 mRNA表达水平显著降低(P<0.05).结论 KCs在脓毒症时肝脏的微循环障碍中起重要作用.     

生物喋呤对烫伤脓毒症大鼠一氧化氮合成的影响

目的：探讨生物喋呤BH4在金黄色葡萄球菌（简称金葡菌）脓毒症中的生物学效应，阐明BH4对一氧化氮（NO）诱生的调控作用。方法：76只Wistar大鼠随机分为正常对照组（n=10)、烫伤对照组（n=10)、烫伤后金葡菌感染组（n=40)和羟基嘧啶（DAHP）拮抗组（n=16)。无菌留取动物肝、肺组织采用RT－PCR方法检测三磷酸鸟苷环水解酶I（GTP－CHI）、诱生型一氧化氮合酶（iNOS)基因表达，同时测定组织中BH4和NO的水平。结果：烫伤后金葡菌感染组动物肝、肺组织中GTP－CHI基因表达明显上调，BH4产生显著增加，iNOS mRNA表达和NO的水平亦明显升高，DAHP组GTP－CHI基因表达上调和BH4合成NO的产生亦明显下降。结论：烫伤后金葡菌感染可诱导体内BH4的合成，BH4在基因和蛋白水平调控着iNOS所介导的NO大量生成，从而对金葡菌脓毒症的病理过程起促进作用。     

Effect of 2,4-diamino-6-hydroxy-pyrimidine on postburn Staphylococcus aureus sepsis in rats

OBJECTIVE: Guanosine triphosphate-cyclohydrolase I (GTP-CHI) is the first and rate-limiting enzyme for the de novo biosynthesis of biopterin. The objective of present study was to observe the effect of 2,4-diamino-6-hydroxy-pyrimidine (DAHP), an inhibitor of GTP-CHI, on the development of postburn Staphylococcus aureus sepsis. DESIGN: A prospective, controlled animal study. SETTING: A research laboratory in a hospital. SUBJECTS: Male Wistar rats. INTERVENTIONS: Fifty-six male Wistar rats were randomly divided into four groups as follows: normal control group (n = 10), scald control group (n = 10), postburn sepsis group (n = 20), and DAHP treatment group (n = 16). In the scald control group, rats were subjected to a 20% total body surface area third-degree scald injury and then were killed at 24 hrs. In the postburn sepsis group (n = 20), rats were inflicted with 20% total body surface area third-degree scald followed by Staphylococcus aureus challenge, and they were further divided into 2- and 6-hr groups. In the DAHP treatment group (n = 16), animals were intraperitoneally injected with a dose of 1 g/kg DAHP before Staphylococcus aureus challenge and then were further divided into 2- and 6-hr groups. Tissue samples from liver, kidneys, lungs, and heart were collected to determine GTP-CHI, inducible nitric oxide synthase, and tumor necrosis factor-alpha messenger RNA expression. Meanwhile, biopterin and nitric oxide concentrations in these tissues were also measured. MEASUREMENTS AND MAIN RESULTS: After the scald injury followed by Staphylococcus aureus challenge, GTP-CHI messenger RNA expression and biopterin concentrations were significantly elevated in various tissues such as liver, heart, kidneys, and lungs, as were the values of inducible nitric oxide synthase messenger RNA expression and nitric oxide formation (p <.01). Pretreatment with DAHP significantly reduced GTP-CHI/biopterin induction (p <.05-.01), and the up-regulation of inducible nitric oxide synthase/nitric oxide was also suppressed. Furthermore, DAHP administration inhibited the gene expression of tumor necrosis factor-alpha. Two hours after septic challenge, tumor necrosis factor-alpha messenger RNA expression in liver, kidneys, and lungs in the DAHP-treated group was 35.7%, 37.3%, and 33.0% of that in the postburn septic group, respectively. Additionally, in animals without DAHP treatment, the 6-hr mortality rate was 55.6% (20 of 36), whereas it was only 25.0% in DAHP-treated animals (4 of 16, p =.08). CONCLUSIONS: Early treatment with DAHP might be a potential strategy to prevent the development of postburn Staphylococcal sepsis, which appears to be associated with down-regulation of biopterin and nitric oxide formation by DAHP.     

JAK/STAT通路介导脓毒症大鼠肝组织高迁移率族蛋白B1 mRNA表达的研究

目的：探讨Janusk激酶／信号转导和转录激活子（JAK／STAT）通路对盲肠结扎穿孔术（CLP）所致脓毒症大鼠肝组织高迁移率族蛋白B1（HMGB1）mRNA表达和急性肝损害的影响。方法：采用CLP模型，大鼠随机分为正常对照组、CLP脓毒症组、JAK2激酶抑制剂AG490和STAT抑制剂雷帕霉素（RPM）处理组。采用逆转录多聚酶链式反应测定肝HMGB1 mRNA，全自动生化分析仪测定肝功能指标。结果：与正常对照组相比，CLP后6－48h HMGB1 mRNA表达显著升高（P＜0．01）；血清天冬氨酸转氨酶（AST）在6－48h增高明显（P＜0．05），丙氨酸转氨酶（ALT）、AST在24h升高非常显著（P＜0．01）。与CLP组相比，AG490预处理组24h HMGB1 mRNA和ALT水平显著下降（P均＜0．01），24h和48h AST亦明显降低（P均＜0．01）；同样，RPM干预后HMGB1 mRNA表达在6h 和24h显著抑制（P＜0．05和P＜0．01），ALT、AST在24h和48h均不同程度下降（P＜0．01和P＜0．05）。结论：抑制JAK／STAT通路活化可明显下调肝组织HMGB1 mRNA表达，并有助于减轻CLP所致急性肝损伤。     

The potential role of Staphylococcal enterotoxin B in rats with postburn Staphylococcus aureus sepsis

Staphylococcal enterotoxin B (SEB) is an important member of the superantigen family, which exerts a number of pathological effects in the human, as well as susceptible animals. The present study was conducted to observe the time course and tissue distribution of SEB in postburn Staphylococcus aureus infection; meanwhile, the relationship between SEB and multiple organ dysfunction was also studied. Eighty-six male Wistar rats were randomly divided into four groups as follows: normal control group (n = 10); scald control group (n = 10); postburn sepsis group (n = 50) in which rats inflicted with 20% total body surface area (TBSA) III degrees scald followed by SEB-producing S. aureus challenge were further divided into 0.5-, 2-, 6-, 12-, and 24-h subgroups, with 10 rats in each subgroup; and SEB monoclonal antibody (MAb) treatment group (n = 16) in which a dose of 4 mg/kg SEB MAb was given intravenously just before S. aureus challenge, and the rats were further divided into 2- and 6-h subgroups. It was found that after thermal injury combined with S. aureus infection, SEB was widely distributed to the liver, kidneys, lungs, and heart, exacerbating the pathophysiology of multiple organ dysfunction induced by postburn sepsis. At the same time, the gene and protein expressions of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were also markedly upregulated in various tissues. Early treatment with SEB-specific MAb-MAb2D(1)-could markedly decrease SEB levels in plasma as well as in various tissues, and could significantly reduce the 6-h mortality rate (17.64% [3/17] vs. 55.6% [20/36], P = 0.02). These data suggested that neutralization of SEB is effective in ameliorating S. aureus sepsis and subsequent multiple organ damage, which might be attributed to its inhibitory effect on inflammatory mediator formation.     

Significance of biopterin induction in rats with postburn Staphylococcus aureus sepsis

It has been demonstrated that biopterin, an essential cofactor of nitric oxide synthase (NOS), plays an important role in the pathogenesis of endotoxin-induced shock, yet its biological significance in gram-positive sepsis remains unclear. In this study, we adopted a rat model of postburn Staphylococcus aureus sepsis to investigate the potential role of biopterin in the pathogenesis of gram-positive sepsis. Wistar rats were inflicted with a 20% total body surface area (TBSA) full-thickness scald injury followed by S. aureus challenge, and then guanosine triphosphate-cyclohydrolase I (GTP-CHI) mRNA expression and biopterin levels in liver, kidneys, lungs, and heart were determined. We found that after S. aureus challenge, GTP-CHI gene expressions and biopterin levels were markedly upregulated in various tissues. Meanwhile, multiple organ dysfunction was induced by S. aureus challenge. It was shown that cardiac GTP-CHI mRNA expression and renal BH(4) levels were positively correlated with MB isoenzyme of creatine kinase (CK-MB) and creatinine (r = 0.892, P = 0.0012 and r = 0.9423, P = 0.0015, respectively). These results suggested that thermal injury combined with S. aureus challenge could induce de novo biosynthesis of biopterin, which might play a role in the development of multiple organ dysfunction syndrome secondary to postburn sepsis.     

烫伤后金黄色葡萄球菌感染致严重脓毒症大鼠模型的建立

目的初步建立烫伤后金黄色葡萄球菌(金葡菌)感染所致严重脓毒症的动物模型。方法雄性Wistar大鼠行20%总体表面积Ⅲ度烫伤,于伤后24小时经腹腔注射对数生长期的金葡菌菌液4ml/kg(浓度为8×10     

烫伤脓毒症大鼠肾脏核转录因子-kB活化与肾损伤关系的研究

目的 研究烫伤脓毒症大鼠肾脏核转录因子-kB（NF-kB）活化与肾损伤的关系。方法采用30％总体表面积Ⅲ度烫伤加内毒素攻击制备烫伤脓毒症大鼠模型。54只Wistar大鼠随机分为正常对照组、烫伤脓毒症1、2、6、12和24h组，烫伤脓毒症1、2和6h＋NF-kB抑制剂吡咯烷二硫基甲酸酯（PDTC）组。采用凝胶电泳迁移率改变分析法（EMSA）检测肾组织NF-kB活性；采用酶联免疫吸附法检测血浆及肾组织中肿瘤坏死因子-α（TNF-α）含量的变化；采用自动生化分析仪检测血肌酐（SCr）和尿素氮（BUN）含量。结果肾组织NF-kB活性于烫伤脓毒症后1h明显增强并达到高峰（P〈0．01），PDTC可显著降低烫伤脓毒症后1h NF-kB的活性。烫伤脓毒症后1h和2h血浆及肾组织中TNF-α水平均明显增高（P均〈0．01），PDTC可显著降低伤后血浆TNF-α水平（P均〈0．01），对肾组织中TNF-α水平影响不明显。烫伤脓毒症后BUN及SCr含量均明显增高（P均〈0．01），PDTC对BUN和SCr含量均无显著影响。结论NF-kB抑制剂可降低烫伤脓毒症大鼠肾组织NF-kB活性，但对肾脏功能无明显保护作用。     

雷帕霉素抑制JAK/STAT通路对大鼠梗阻性黄疸肝肿瘤坏死因子-α表达的影响

目的探讨雷帕霉素抑制JAK/STAT信号通路在大鼠梗阻性黄疸中对肿瘤坏死因子-α(TNF-α)表达的影响。方法采用胆总管结扎方法建立大鼠梗阻性黄疸模型,将54只SD大鼠随机分为假手术组(A组)18只,梗阻性黄疸+STAT抑制剂雷帕霉素处理组(B组)18只,梗阻性黄疸组(C组)18只,A、B、C三组分别于术后1、3、5d处死大鼠,每个时间段6只。监测各时间段大鼠肝功能酶学变化,Westernblot法检测受试样品TNF-α蛋白表达,RT-PCR测各组不同时间段TNF-αmRNA的表达。结果与假手术组比较,两梗阻性黄疸组肝功能酶学差异显著,TNF-α蛋白及基因表达升高明显,与雷帕霉素干预组比较,梗阻性黄疸组TNF-α蛋白及基因表达升高明显,有统计学差异(P<0.01)。结论雷帕霉素可能通过抑制JAK/STAT信号转导通路降低梗阻性黄疸大鼠TNF-α表达,减少对肝细胞的损伤,对肝脏起到一定的保护作用。     

休克期切痂对烫伤大鼠肝HMGB1表达及肝功能的影响

目的　探讨休克期切痂对烫伤大鼠肝组织高迁移率族蛋白B1(HMGBl)表达及肝脏功能影响。方法　 30 %Ⅲ度烫伤Wistar大鼠随机分为 2 4h和 72h切痂植皮组。RT PCR和免疫组化染色法检测肝脏HMGBlmRNA/蛋白表达 ,同时检测血浆AST、ALT含量。结果　大鼠烫伤后肝组织HMGB1mRNA表达量增加 1～ 2 5倍 ,2 4h切痂组伤后 8d其水平较烫伤对照和 72h切痂组显著减少 (P <0 0 5 )。烫伤后大鼠肝细胞和枯否细胞HMGB1表达阳性率较正常大鼠均显著升高 (P <0 0 1) ,2 4h切痂组 4、 8dHMGB1表达阳性细胞数较烫伤对照和 72h切痂组均显著减少 (P <0 0 1)。同时 ,烫伤大鼠血浆AST和ALT水平升高 (P<0 0 5 ) ,而 2 4h切痂组伤后 4、 8d较烫伤对照组和 72h切痂组显著降低 (P <0 0 1)。结论　烫伤大鼠休克期切痂能够下调肝组织HMGB1表达 ,局部HMGB1诱生参与了肝损伤的病理生理过程。