急性心肌梗死大鼠心脏一氧化氮合酶表达的改变

目的 通过建立大鼠心肌梗死模型，观察急性心肌梗死对大鼠心脏内皮型一氧化氮合酶mRNA和诱导型一氧化氮合酶蛋白表达的影响。方法48只健康成年SD大鼠（体重200～250g）随机分为假手术组和缺血组，取1、2、8和24h四个不同时间点观察。采用开胸结扎冠状动脉左前降支建立心肌缺血模型，逆转录聚合酶链反应检测大鼠心肌梗死后1、2及24h三个时段缺血心肌内皮型一氧化氮合酶mRNA的表达；免疫组织化学染色检测冠状动脉结扎后8h缺血心肌诱导型一氧化氮合酶蛋白的表达。结果冠状动脉结扎后2h，缺血组大鼠缺血心肌组织内皮型一氧化氮合酶mRNA表达下降（P〈0．05），并持续至结扎后24h；结扎后24h组内皮型一氧化氮mRNA的表达与结扎后2h组相比无显著性差异（P〉0．05）。冠状动脉结扎后8h，梗死区存活心肌组织细胞诱导型一氧化氮合酶蛋白大量表达，而假手术组未见诱导型一氧化氮合酶蛋白表达。结论正常大鼠心肌组织有内皮型一氧化氮合酶基因表达，无诱导型一氧化氮合酶蛋白表达。在心肌梗死早期缺血心肌内皮型一氧化氮合酶mRNA表达减少。心肌急性缺血刺激早期诱导大鼠缺血心肌组织诱导型一氧化氮合酶蛋白大量表达。     

大鼠棉花烟雾吸入性肺损伤中的氧化应激

目的 探讨大鼠棉花烟雾吸入性肺损伤中的氧化应激反应机制.方法 18只雄性SD大鼠随机分成对照组、6h组、24 h组,每组6只.复制大鼠棉花烟雾吸入性肺损伤模型,6h组、24 h组大鼠分别在烟雾吸入后6h或24 h行安乐死,ELISA法检测大鼠肺组织丙二醛(MDA)、谷胱甘肽(GSH)、一氧化氮(NO)、诱导型一氧化氮合酶(iNOS)、γ-谷氨酰半胱氨酸合成酶(γ-GCS)浓度,荧光定量PCR法行肺组织iNOS mRNA、γ-GCS mRNA定量.结果 6h组、24 h组大鼠肺组织匀浆中的MDA、NO、iNOS、γ-GCS浓度、iNOS mRNA和γ-GCS mRNA的相对表达量均高于对照组,且NO浓度、iNOSmRNA和γ-GCS mRNA的相对表达量24 h组高于6h组(P值均＜0.05);而6h组和24 h组GSH浓度均低于对照组,且24 h组低于6h组(P值均＜0.05).结论 在大鼠棉花烟雾吸入性肺损伤中,氧化应激反应加剧,同时抗氧化体系的激活不足以对抗氧化应激损伤,氧化/抗氧化体系失衡,导致肺损伤逐渐加重.     

内皮细胞中血管紧张素Ⅱ对诱导型一氧化氮合酶表达影响及干预的实验研究

目的 探讨在内皮细胞中血管紧张素Ⅱ对诱导型一氧化氮合酶表达的影响以及血管紧张素Ⅱ一型受体（AT1）、血管紧张素Ⅱ二型受体（AT2）和核因子-kappaB在其中的作用。方法 体外培养人脐静脉内皮细胞,用血管紧张素Ⅱ单独和与AT1、AT2、核因子-kappaB的抑制剂联合干预细胞后,用RT-PCR检测诱导型一氧化氮合酶mRNA表达,Western blot检测诱导型一氧化氮合酶蛋白表达,电泳迁移率变动分析（EMSA）检测核因子-kappaB的活性。结果 在血管紧张素Ⅱ干预2h后核因子-kappaB活性增强（P〈0．05）,5h后诱导型一氧化氮合酶的mRNA和蛋白表达增加（P〈0．05）,核因子-kappaB和AT1的抑制剂能抑制这种增加（P〈0．05）,AT2则无此作用。结论 在内皮细胞中血管紧张素Ⅱ与AT1结合后激活核因子-kappaB,后者的激活引起诱导型一氧化氮合酶表达的增强,从而增加了心血管系统的炎性反应。     

肿瘤坏死因子α和血管紧张素Ⅱ干预内皮细胞后细胞凋亡和诱导型一氧化氮合酶的表达

目的探讨肿瘤坏死因子α和血管紧张素Ⅱ在导致内皮细胞凋亡过程中诱导型一氧化氮合酶的表达变化及核因子κB的作用。方法核因子κB抑制剂吡咯烷二硫代氨基甲酸盐预处理和未预处理原代培养的脐静脉内皮细胞,用肿瘤坏死因子α和血管紧张素Ⅱ分别进行干预,逆转录聚合酶链反应检测诱导型一氧化氮合酶mR-NA的表达,免疫印迹法检测诱导型一氧化氮合酶和IκBα的蛋白表达,电泳迁移率分析检测核因子κB的活性,TUNEL法检测细胞凋亡。结果在10μg/L肿瘤坏死因子α和1μmol/L血管紧张素Ⅱ的干预下,核因子κB的活性显著增加(P<0.05),诱导型一氧化氮合酶mRNA和蛋白的表达与对照组比较显著增加(P<0.05),细胞凋亡发生显著增加(P<0.05);吡咯烷二硫代氨基甲酸盐抑制肿瘤坏死因子α和血管紧张素Ⅱ引起的细胞凋亡和诱导型一氧化氮合酶表达的增加。结论在肿瘤坏死因子α和血管紧张素Ⅱ作用于内皮细胞时,通过降解IκBα引起诱导型一氧化氮合酶的核转位,后者可引起诱导型一氧化氮合酶表达上调和细胞凋亡。     

肝脏X受体激活对α-GalCer诱导的小鼠肝损伤保护机制探讨

肝脏X受体（LXR）属于核受体超家族成员,对脂类代谢相关基因的转录调控起关键作用,同时具有调节免疫反应和抗炎效应。目的：研究LXR激活对仅．GalCer诱导的小鼠肝损伤保护作用的可能机制。方法：15只C57BL／6J小鼠随机分为正常对照组、α-GalCer模型组和LXR治疗组,后两组以仅α-GalCer腹腔注射诱导肝损伤模型．LXR治疗组于造模前连续7d腹腔注射LXR激动剂T0901317。造模6h后处死小鼠,行肝组织病理学检查和血清AIJT、AST水平检测,免疫组化染色检测肝组织白细胞介素-6（IL-6）表达．蛋白质印迹法检测肝内P13K／Akt／NF—κB信号通路激活情况,实时RT-PCR检测肝组织肿瘤坏死因子-α（TNF-α）、诱导型一氧化氮合酶（iNOS）mRNA表达。结果：与正常对照组相比,α-GalCer模型组小鼠肝损伤明显。血清转氨酶水平升高,肝组织IL-6、TNF-α仅、iNOS表达上调．P13K／Akt／NF—κB信号通路激活。LXR治疗组肝损伤和血清转氨酶水平较α-GalCer模型组显著改善,肝组织炎症介质表达下调,P13K／Akt／NF—κB信号通路激活受抑。结论：LXR激活可调节免疫反应,抑制肝脏炎症,从而显著减轻α-GalCer诱导的小鼠肝损伤．其机制可能与抑制P13K／Akt／NF—κB信号通路激活有关。     

辛伐他汀对非酒精性脂肪性肝病大鼠肝组织纤维化的影响及分子机制

目的 探讨辛伐他汀对非酒精性脂肪性肝病(NAFLD)肝组织纤维化模型及肝星状细胞的作用及其分子机制.方法 ①体内实验应用高脂饮食建立NAFLD肝组织纤维化大鼠模型,并用辛伐他汀干预,RT-PCR法和Western印迹检测大鼠肝组织中内皮型一氧化氮合酶(eNOS)、诱导型NOS(iNOS)和Ⅰ型胶原mRNA和蛋白的表达.②体外实验采用促进脂肪细胞分化的培养基诱导人肝星状细胞株LX-2细胞获得静止表型,分别用转化生长因子β1( TGF-β1)、NOS抑制剂亚硝基左旋精氨酸甲酯(L-NAME)、辛伐他汀、TGF-β1+辛伐他汀、L-NAME+辛伐他汀处理静止型LX-2细胞,RT-PCR法和Western印迹检测各组LX-2细胞中eNOS、iNOS、α-平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原mRNA及蛋白的变化.结果 ①随造模时间延长,模型组大鼠肝组织eNOS mRNA和蛋白表达逐渐减少,iNOS和Ⅰ型胶原mRNA和蛋白表达逐渐增加,与正常对照组比较差异有统计学意义(P分别＜0.05和0.01).与24周末模型组相比,辛伐他汀干预组大鼠肝组织eNOS mRNA和蛋白的表达分别增加(0.30±0.02比0.24±0.01和0.45±0.04比0.22±0.02,P值均＜0.05),iNOS mRNA和蛋白的表达分别减少,Ⅰ型胶原mRNA和蛋白表达分别减少(P值均＜0.05).模型组大鼠肝组织中eNOS mRNA和蛋白表达与Ⅰ型胶原mRNA和蛋白表达均呈负相关(P值均＜0.01);iNOS mRNA和蛋白表达与Ⅰ型胶原mRNA和蛋白表达均呈正相关(P值均＜0.01).②体外培养LX-2细胞中,L-NAME能抑制LX-2细胞活化,减少eNOS和iNOS的表达,增加α-SMA和Ⅰ型胶原表达,与TGF-β1作用一致;辛伐他汀能直接增加静止型及活化型LX-2细胞中eNOS的表达,减少iNOS的表达,维持其静止表型,抑制其活化.结论 辛伐他汀通过增加LX-2细胞中eNOS表达,减少iNOS表达,减少α-SMA和Ⅰ型胶原生成,抑制或逆转肝纤维化发生和发展.     

肝炎患者血清一氧化氮和一氧化氮合酶水平变化及其临床意义

目的 探讨血清一氧化氮水平、总一氧化氮合酶和诱导型一氧化氮合酶活力与病毒性肝炎的关系.方法 用生化方法 检测对照组、中度慢性乙型肝炎、肝硬化、慢性重症肝炎及乙戊肝重叠感染患者血清一氧化氮、总一氧化氮合酶和诱导型一氧化氮合酶水平.结果 中度慢性乙型肝炎、肝硬化及乙戊肝重叠感染患者血清一氧化氮水平、总一氧化氮合酶和诱导型一氧化氮合酶活力与对照组比较明显升高,慢性重症肝炎患者血清一氧化氮水平、总一氧化氮合酶和诱导型一氧化氮合酶活力与对照组比较明显降低(P＜0.05).结论 一氧化氮、总一氧化氮合酶和诱导型一氧化氮合酶在病毒性肝炎发病中具有重要作用,并在一定程度上与肝损害程度相关.     

组织因子、Egr-1及Sp1在大鼠狭窄颈动脉内皮细胞的表达

目的研究在体动物颈动脉狭窄处内皮细胞组织因子基因的切应力性表达规律及其机制。方法实验分为对照组和颈动脉狭窄组,套扎法建立左颈总动脉狭窄模型,狭窄组又分为0.5 h1、h3、h6、h、12 h1、d、3 d和7 d8个时间点,术后不同时间点用原位杂交和免疫组织化学法,检测组织因子、Egr-1和Sp1的mRNA和蛋白表达,用图像分析系统测定内膜平均灰度,进行统计学分析。结果对照组内皮细胞组织因子、Egr-1及Sp1的mRNA转录和蛋白合成弱;狭窄30 min后,与对照组比较内皮细胞胞质组织因子基因mRNA转录和蛋白合成升高(P<0.05),内皮细胞胞核和胞质Egr-1和Sp1基因mRNA转录和蛋白合成均增加(P<0.05),但以Egr-1增加更显著(P<0.05),其变化趋势与组织因子基因mRNA转录及蛋白合成的变化趋势相同。组织因子基因mRNA转录和蛋白合成于6 h达到峰值,Egr-1基因mRNA转录和蛋白合成于3 h达到峰值,Sp1基因mRNA转录和蛋白合成于1 h达到峰值,与对照组比较差异有显著性(P<0.05)。结论颈动脉狭窄时,切应力能够诱导动脉狭窄处内皮细胞组织因子基因表达,其表达与内皮细胞转录因子Egr-1和Sp1介导有关。     

卡托普利晚期预处理对人内皮细胞缺氧复氧损伤时内皮素1和一氧化氮合酶表达的影响

观察缺氧复氧损伤时内皮细胞表达内皮素、一氧化氮合酶和一氧化氮的变化 ,并探讨卡托普利晚期预处理对内皮细胞在缺氧复氧损伤时三者的影响及机制。选用体外培养的第 3代人脐静脉内皮细胞 ,设正常对照组、单纯缺氧组、缺氧复氧组、卡托普利预处理组、卡托普利 +缓激肽B2 受体阻断剂组、卡托普利 +蛋白激酶C阻断剂组和卡托普利 +核因子κB阻断剂组 ,然后提取总RNA ,运用半定量逆转录—聚合酶链反应检测内皮素、一氧化氮合酶的mRNA表达。并利用分光光度计检测总一氧化氮合酶和一氧化氮蛋白的表达。结果发现 ,内皮素的灰度值在单纯缺氧组、缺氧复氧组均升高 ,在卡托普利组降低 ,而在三种阻断剂组均升高 ;诱导型一氧化氮合酶和内皮型一氧化氮合酶灰度值的变化规律与内皮素相反 ,其中诱导型一氧化氮合酶的变化较为轻微。与对照组相比 ,单纯缺氧组和缺氧复氧组一氧化氮合酶和一氧化氮有不同程度的降低 (P <0 .0 1) ;与单纯缺氧组和缺氧复氧组相比 ,卡托普利组一氧化氮合酶和一氧化氮均明显升高 (P <0 .0 1) ;与卡托普利组相比 ,3种阻断剂均可使一氧化氮合酶和一氧化氮的表达下降 (P <0 .0 1) ,而与缺氧复氧组相比表达升高 (P <0 .0 1)。结果提示 ,缺氧复氧可以使内皮细胞表达的内皮素增加 ,一氧化氮合酶降低 ,     

茶多酚减轻代谢综合征大鼠胰岛β细胞炎性损伤的机制研究

通过高糖高脂饮食诱导建立SD大鼠代谢综合征(MS)模型.茶多酚干预10周后大鼠空腹血糖、甘油三酯、胆固醇、低密度脂蛋白胆固醇、游离脂肪酸水平均较MS组明显下降(均P＜0.05),茶多酚组胰腺组织肿瘤坏死因子α、干扰素、诱导型一氧化氮合酶的mRNA和蛋白表达较MS组明显下降(均P＜0.05),白细胞介素1β蛋白表达也明显降低(P＜0.05).电镜观察茶多酚组大鼠胰岛β细胞的分泌颗粒较MS组增多,细胞器结构破坏减轻.提示茶多酚可通过抑制炎性细胞因子的产生,保护胰岛β细胞免受损伤.     

大黄素对实验性淤胆型肝炎的治疗作用及其机制

目的 探讨大黄素对淤胆型肝炎的治疗作用及其机制.方法 S D大鼠分为5组:大黄素组,熊去氧胆酸组、地塞米松组、模型组、正常对照组,除正常对照组外,其余4组均给予α-异硫氰酸萘酯50 mg/kg一次灌胃大鼠建立淤胆型肝炎动物模型,并给予相应的药物干预,造模后24、48、72 h分别处死大鼠.免疫组织化学法检测肝组织中核因子κB表达.实时荧光定量PCR检测肝组织中早期生长反应因子1、中性粒细胞趋化因子1,巨噬细胞炎症蛋白-2 mRNA表达,Westernblot检测肝组织中细胞间黏附分子1蛋白表达.双抗体夹心酶联免疫吸附法检测肝组织肿瘤坏死因子α、白细胞介素6含量,硫代巴比妥酸比色法、黄嘌呤氧化酶法及比色法分别检测肝组织中丙二醛、超氧化物歧化酶、髓过氧化物酶含量.结果 (1)造模后24、48,72 h,大黄素组血清总胆红素分别为(32.8±3.7)umol/L、(61.0±16.4)μmol/L和(10.8±4.5) μmol/L,直接胆红素分别为(26.0±3.1)lamol/L、(49.4±18.2)μmol/L和(8.0±3.0)μmol/L;ALT分别为(313.7±49.8)U/L、(664.3±96.5)U/L和(200.3±60.3)U/L,均明显低于模型组,P值均<0.01,差异有统计学意义.(2)造模后24、48 h,大黄素组的核因子κ B p65核表达阳性细胞百分率分别为24.1%和9.8%,模型组分别为48.3%和26.5%,P值均<0.01,差异有统计学意义.(3)造模后24、48 h,大黄素组的细胞因子诱导的中性粒细胞趋化因子1、巨噬细胞炎症蛋白-2mRNA表达、细胞间黏附分子1蛋白表达、肿瘤坏死因子α、白细胞介素6含量均较模型组显著降低(P值均<0.01).结论 大黄素可显著改善实验性淤胆型肝炎大鼠的肝功能,其作用机制可能与抑制NF-κB信号通路有关.     

钙敏感受体在淤胆型肝炎小鼠肝脏组织中的表达

[目的]探讨钙敏感受体（Calcium-sensingreceptor,CaR）在淤胆型肝炎小鼠肝组织中的表达。[方法]采用ANIT（80mg／kg,po）制备小鼠淤胆型肝炎模型,检测给予ANIT24h、48h后小鼠血清ALT、ALP及BA水平,HE染色观察肝脏病理组织学改变,免疫组化检测CaR在淤胆型肝炎小鼠肝组织中的表达。[结果]给予ANIT24h、48h后,小鼠血清ALT、ALP及BA水平逐渐升高,48h后明显上升;病理结果显示48h后,肝细胞坏死明显;免疫组化结果显示淤胆型肝炎小鼠肝组织中CaR的表达明显增强。[结论]CaR在淤胆型肝炎小鼠肝脏组织中存在高表达,且可能与淤胆的发生有关。     

Chemokines and left ventricular function in patients with acute myocardial infarction

BACKGROUND: Leukocytes are activated in the inflammatory process involving locally atherosclerotic lesions through adhesive molecules attaching to the surface of endothelial cells, especially during acute myocardial infarction. The aim of the study was to assess MCP-1, MIP-1alpha, and RANTES serum levels in patients with STEMI and to correlate them with the severity of left ventricle (LV) dysfunction. METHODS: Forty patients were initially divided into two groups, with group 1 having an ejection fraction (EF) above 40% and group 2 an EF of 40% or less. Next, the patients were divided on the basis of wall motion score index (WMSI): group 3 had a WMSI of 1.3 or lower and group 4 had a WMSI above 1.3. A control group of ten volunteers was also included in the study. Serum samples were taken at admission as well as 3, 24, 48, 72 h, and 7 days after. RESULTS: The baseline serum levels of MCP-1 and RANTES in group 1 were significantly higher than in the controls (p<0.05 and p<0.005, respectively). The highest concentrations of chemokines were observed 3 h after admission. The serum levels of MIP-1alpha on admission and 3 h later were significantly higher in group 1 than in group 2 (p<0.03 and p<0.01, respectively). Maximum MIP-1 concentrations were observed 3 h after admission in group 3 and 24 h after admission in group 4 (p<0.006). In group 1, MIP-1alpha 3 h after admission correlated positively with the EF (r=0.444, p<0.05). In group 1 there was a negative correlation between MIP-1alpha concentration 3 h after admission and LV end-diastolic dimension (r=-0.492, p<0.02). CONCLUSIONS: Patients with myocardial infarction with an elevated ST segment had a significant increase in MCP-1, MIP-1alpha, and RANTES serum levels.     

Kinetics of chemokines in acute myocardial infarction

BACKGROUND: Chemokines are supposed to play an important role in the activation of monocytes and in the development of atherosclerosis. There are also suggestions that chemokine-mediated enhanced coagulability may be related to the pathogenesis of acute coronary syndromes.Aim. To assess the kinetics of 3 chemokines: Monocyte Chemoattractant Protein-1 (MCP-1), Macrophage Inflammatory Protein-1alfa (MIP-1alpha) and Regulated on Activation Normal T cell Expressed and Secreted (RANTES) in patients with ST-elevation myocardial infarction (STEMI). METHODS: The study group consisted of 40 patients (pts) with STEMI who were divided into 2 groups -- 16 pts with anterior MI (AMI) and 24 pts with inferior or lateral MI (IMI). According to the type of received therapy, the pts were divided into 2 other groups: group A -- 30 pts treated with thrombolytic agents or primary angioplasty and group B -- 10 pts without recanalisation therapy. The control group consisted of 10 healthy volunteers. Blood samples for MCP-1, MIP-1alpha and RANTES serum levels was taken on admission and 3 h, 24 h, 48 h, 72 h and 7 days afterwards. RESULTS: The baseline MCP-1 and RANTES levels were significantly higher in pts with STEMI than in controls (1068.9 vs 880.9 pg/ml, p<0.05; 50.8 vs 33.9 pg/ml, p<0.005). In pts with STEMI, peak levels of MCP-1 and MIP-1alpha were significantly higher 3h than 24h from admission (MCP-1 1274.4 vs 1097.4 pg/ml, p<0.02; MIP-1alpha 39.2 vs 22.0 pg/ml, p<0.01). In all STEMI pts there was a positive correlation between MIP-1alpha 3h and left ventricular ejection fraction (LVEF) (r=0.455, p<0.05) and a negative correlation between MIP-1alpha 3h and LV end-diastolic diameter (LVEED) (r=-0.453, p<0.05). A significant positive correlation between TnI level and chemokines in both AMI and IMI patients was detected, being the highest in AMI and IMI groups when MIP-1alpha 24 h and TnI were compared (R=0.852, p<0.003 and R=0.646, p<0.0001). In pts with IMI, a positive correlation between RANTES, MIP-1alpha 3h and LVEF was found (R=0.322, p<0.03 and R=0.399, p<0.008). In group A, all MIP-1alpha values were significantly higher than in group B. Also, peak MIP-1alpha levels significantly differed between groups A and B (44.8 vs 8.3 pg/ml, p<0.006). In pts from group B, a negative correlation between MCP-1 measured an admission and LVEF was found (R=-0.690, p<0.05). CONCLUSIONS: We found a significant elevation of chemokines in the early period of acute MI. The correlations between different parameters suggest, that chemokines may serve as new parameters of immune activation in STEMI and also may play the dominant role in the cardiac inflammatory response and subsequent repair processes.     

IL-1 regulates in vivo C-X-C chemokine induction and neutrophil sequestration following endotoxemia

The influx of neutrophils into tissues in response to inflammatory stimuli involves C-X-C chemokines. Interleukin-1 (IL-1) stimulates chemokine production in vitro, but its role in vivo on chemokine production is not as clearly understood. We hypothesized that IL-1 mediates in vivo tissue C-X-C chemokine production induced by systemic lipopolysaccharide (LPS). IL-1 activity was blocked by IL-1 receptor antagonist (IL-1Ra). Rats were injected with Salmonella typhi LPS (0.5 mg/kg) with and without prior administration of IL-1Ra. Cytokine-induced neutrophil chemoattractant-1 (CINC-1) and macrophage inflammatory protein-2 (MIP-2) protein and mRNA levels, tissue neutrophil accumulation, and indices of organ injury were measured. LPS administration resulted in increased plasma, lung, and liver IL-1beta that was decreased by Il-1Ra. LPS also induced an increase in plasma, lung, and liver CINC-1 and MIP-2 protein and mRNA. However, IL-1Ra had no effect on LPS-induced plasma or lung tissue CINC-1 levels. In contrast, IL-1Ra pretreatment did significantly decrease CINC-1 protein expression in the liver (45% decrease) and MIP-2 protein expression in plasma (100% decrease), lung (72% decrease) and liver (100% decrease) compared to LPS- treated controls. Steady-state mRNA levels by Northern blot analysis of both CINC-1 and MIP-2 in lung and liver were similar to the protein findings. Pretreatment with IL-1Ra also resulted in a 47% and 59% decrease in lung and liver neutrophil accumulation, respectively, following LPS. In addition, indices of both lung and liver injury were decreased in animals pretreated with IL-1Ra. In summary, LPS induces IL-1beta and MIP-2 expression in the lung and liver, both of which are IL-1 dependent. Although lung neutrophil accumulation in both lung and liver after LPS is also IL-1 mediated, lung CINC-1 levels were unaffected by IL-1Ra. These data suggest that IL-1 regulates tissue chemokine expression and neutrophil accumulation after LPS.     

Expression of macrophage inflammatory protein-1α in Kupffer cells following liver ischemia or reperfusion injury in rats

AIM: To explore the expression of macrophage inflammatory protein-1alpha (MIP-1alpha) in Kupffer cells (KCs) following liver ischemia/reperfusion injury IRI in rats. METHODS: Forty male SD rats were divided randomly into five groups. A model of partial warm ischemia/reperfusion injury in the rat liver was established. KCs were isolated and incubated one hour, six hours, 12 h, and 24 h after the reperfusion. Tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in the supernatants were measured by ELISA. MIP-1alpha in KCs was detected by immunocytochemical and RT-PCR. RESULTS: No or few MIP-1alpha protein and mRNA were expressed in the KCs of the control group. Its expression in the IRI group had a significant increase after the reperfusion (P < 0.05), which was contrary to the control group. CONCLUSION: The active behavior of the MIP-1alpha gene in KCs following liver ischemia/reperfusion injury is assumed to be one of the major causes for the hepatic ischemia/reperfusion injury.     

CC-chemokine receptor 6 and its ligand macrophage inflammatory protein 3alpha might be involved in the amplification of local necroinflammatory response in the liver

It is not fully understood how antigen-specific or-nonspecific T cells migrate into the liver in various liver diseases. Macrophage inflammatory protein (MIP)-3alpha is a chemokine that is expressed mostly in the liver, and the receptor CCR6 is reported to be expressed on memory T cells. In the present study, we focused on the expression of CCR6 on T cells from peripheral blood (PB) and inflamed liver, and analyzed the involvement of MIP-3alpha and CCR6 in the immunopathogenesis of liver diseases. Intrahepatic T cells showed significantly (P <.0001) higher percentages of CCR6(+)CD4(+) T cells compared with PB, which is significantly (P =.037) correlated with the necroinflammatory response in the liver. Most of intrahepatic CCR6(+)CD4(+) cells were also positive for CCR5, which is known to express on T-helper 1 cells. MIP-3alpha was stained in the cells located near piecemeal necrosis, where dendritic cells (DCs) are often observed, and coculture of activated DCs with apoptotic cells induced MIP-3alpha production from the DCs. These data suggest that MIP-3alpha is produced by periportal DCs and/or macrophages after necroinflammatory response, leading to the recruitment of activated T cells into the liver. This process could be important to augment the local immune response in the livers of various liver diseases. The finding might be important not only for the understanding of immunopathogenesis of liver diseases but also for the therapeutic strategy to control the local immune response in the liver.     

Influence of D-galactosamine and alpha-naphthylisothiocyanate on the activities of some intestinal enzymes

The activities of lactase, sucrase, maltase and gamma-glutamyl transferase (gamma-GT) were determined in homogenates of rat jejunal mucosa 24 h after acute administrations of D-galactosamine (GALN) (1.855 mmol/kg; i.p. injection) and alpha-naphthyl-isocyanate (ANIT) (0.540 mmol/kg; given by gastric tube). The animals were fasted either 24 h or 72 h prior to sacrifice. In rats fasted only 24 h, GALN treatment resulted in a pronounced decrease in lactase and in a moderate elevation of sucrase and maltase. ANIT clearly reduced lactase and, to a lesser extent, sucrase, while it increased maltase. Seventy-two hour fasting has a modifying role. All disaccharidase activities tended to decrease, except for maltase in the ANIT treated group, where an increase was recorded. gamma-GT showed no significant changes after either GALN or ANIT treatment in rats fasted 24 h. However, the 72-hour food deprivation diminished it in ANIT intoxication. It is obvious that the intestinal enzymes are influenced by the hepatic damage produced by GALN and ANIT.     

Chemokine and Cell Adhesion Molecule mRNA Expression and Neutrophil Infiltration in Lipopolysaccharide-Induced Hepatitis in Ethanol-Fed Rats

Neutrophil infiltration is a feature of alcoholic hepatitis (AH), and although the mechanism by which this occurs is unclear, it may involve a chemotactic gradient. We used lipopolysaccharide (LPS) to induce, in ethanol-fed rats, liver damage similar to that seen in AH. To our knowledge, this study is the first to examine the effect of ethanol on LPS-stimulated chemokine mRNA expression in this model. Hepatic cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, monocyte chemoattractant protein-1 (MCP-l), macrophage inflammatory protein (MIP)-1 β, MIP-2, and eotaxin mRNA levels were elevated 1 to 3 hr post-LPS in both groups. Maximal expression of MIP-2 and MCP-1 mRNA was higher in ethanol-fed rats 1 hr post-LPS, whereas CINC-2 mRNA expression was elevated above controls at 12 to 24 hr. Hepatic intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 mRNA levels were elevated in both groups at 1 hr, whereas L-selectin expression in ethanol-fed rats was elevated above controls at 12 to 24 hr. Hepatic neutrophil infiltration was highest during maximal hepatocyte necrosis. These data suggest that cell adhesion molecules, in conjunction with elevated cytokines and the subsequently induced chemokines, may assist in the formation of a chemotactic gradient within the liver, causing the neutrophil infiltration seen both in this model and possibly in AH.     

Effect of prostacyclin (PGI2) and a prostaglandin analogue BW 245C on galactosamine-induced hepatic necrosis

The reported cytoprotective effects of prostaglandins against noxious stimuli in the liver was the basis for the present investigations of the effects of prostacyclin (PGI2) and a prostaglandin analogue (BW 245C) in an animal model of severe liver failure. Rats were given galactosamine at two dose levels and the prostaglandins were given in repeated doses from 0 to 6 h during the development of the liver damage or in another group from 24 to 30 h at the time of maximal liver injury. For PGI2 significant cytoprotection was found as assessed by a reduction in blood Normotest at 24, 48 and 72 h (P less than 0.05) and the plasma level of aspartate aminotransferase at 24 and 48 h (P less than 0.02) and the lysosomal markers N-acetyl-beta-glucosaminidase at 24, 48 and 72 h (P less than 0.001) and cathepsin D at 48 h (P less than 0.005) as compared to appropriate controls. Early administration of PGI2 reduced the mortality rate from 63% in the control group to 0% (P less than 0.01) in the treated group, but no significant effects were found when either compound was given later in the 24-h to 30-h period.