槲皮素对异丙肾上腺素所致大鼠心肌肥厚的影响

目的　研究槲皮素（ Ｑｕｅ） 对异丙肾上腺素（ Ｉｓｏ） 所致大鼠心肌肥厚的抑制作用及作用机制。方法　 Ｉｓｏ ００２ ｍｇ·ｋｇ－ １ ,每日两次,连续ｓｃ ６ ｗｋ ,形成大鼠心肌肥厚模型,分别测定心脏各重量参数、心肌过氧化脂质（ Ｌ Ｐ Ｏ） 含量、超氧化物歧化酶（ Ｓ Ｏ Ｄ） 活性及心肌 Ｃａ２ ＋ 和主动脉 Ｃａ２ ＋ 含量,培养乳鼠心肌细胞,应用 Ｆｕｒａ ２／ Ａ Ｍ 钙荧光指示剂技术测定心肌细胞内游离钙浓度。结果　 Ｉｓｏ 连续ｓｃ ６ ｗｋ 后,心肌和左心室重量明显增加,心肌 Ｌ Ｐ Ｏ 含量显著增加, Ｓ Ｏ Ｄ 活性下降,心肌 Ｃａ２ ＋ 和主动脉 Ｃａ２ ＋ 含量明显增加,给 Ｑｕｅ ７５ ｍｇ·ｋｇ－ １ ,１５０ ｍｇ·ｋｇ － １ 和维拉帕米１０ ｍｇ·ｋｇ － １ 后均能明显减轻心肌肥厚,降低 Ｌ Ｐ Ｏ 含量,增加 Ｓ Ｏ Ｄ 活性,降低心肌 Ｃａ２ ＋和主动脉 Ｃａ２ ＋ 的含量,应用 Ｆｕｒａ ２／ Ａ Ｍ 钙荧光指示剂技术发现 Ｉｓｏ 和 Ｈ２ Ｏ２ 能引起培养乳鼠心肌细胞内游离钙浓度明显升高。槲皮素对心肌细胞静息钙无明显影响,能抑制 Ｉｓｏ和 Ｈ２ Ｏ２ 致培养乳鼠心肌细胞内游离钙浓度的升高。结论　 Ｑｕｅ 能抑制 Ｉｓｏ 所引起的心肌肥厚, 该作用与清     

人参皂甙对顺铂所致大鼠肾损害的保护作用

通过药物与肾皮质薄片直接孵育法和注射给药法观察了人参皂甙（Ｇｉｎ）对顺铂（ＣＰ）所致大鼠肾损害的作用。结果表明：ＣＰ１．０ｍｍｏｌ·Ｌ￣（－１）在含有对氨基马尿酸（ＰＡＨ）的生理盐水溶液中与肾薄片孵育１２０ｍｉｎ，导致薄片中ＰＡＨ的蓄积明显减少，Ｇｉｎ８０ｍｇ·Ｌ￣（－１）增加ＰＡＨ的蓄积并抑制ＣＰ引起的ＰＡＨ蓄积减少。ＣＰ７．５ｍｇ·ｋｇ￣（－１）ｉｐ导致时间依赖性的血浆尿素氮（ＢＵＮ）升高，肾皮质组织中超氧化物歧化酶（ＳＯＤ）活性降低和脂质过氧化代谢产物丙二醛（ＭＤＡ）升高Ｇｉｎ５０ｍｇ·ｋｇ￣（－１）每日２次ｉｐ抑制ＣＰ所致的ＢＵＮ和ＭＤＡ升高及ＳＯＤ活性降低，推测Ｇｉｎ对ＣＰ所致大鼠肾损害的保护作用可能与其增强肾小管细胞的内在反应性和抗脂质过氧化作用有关。     

维生素E对氯丁二烯所致大鼠肝损害的预防作用

给大鼠ｉｇ维生素Ｅ１５０ｍｇ·ｋｇ－１·ｄ－１，３０ｍｉｎ后ｉｐ氯丁二烯（ＣＢＤ）８０ｍｇ·ｋｇ－１·ｄ－１，持续３ｗｋ，能明显防止由单独ｉｐＣＢＤ而引起的肝细胞色素Ｐ４５０，氨基比林脱甲基酶活性的降低及肝内脂质过氧化产物丙二醛含量升高；还可使线粒休与微粒体α－生育酚含量大幅度升高，并使肝受损指标血清甘胆酸含量下降，病理所见肝细胞变性坏死亦明显减轻。离休肝细胞以ＣＢＤ染毒发现，胞内游离钙浓度明显升高，并有明显的剂量依赖关系。     

MN 9202抗角叉菜胶引起的大鼠血栓形成作用及其对血液流变学的影响

目的：观察新的二氢吡啶类钙通道阻滞剂２，６－二甲基－４－（３－硝基苯基）－１，４－二氢－３，５－吡啶二羧酸－３－甲酯－５－正戊酯（ＭＮ９２０２）对角叉菜胶引起的大鼠血栓形成的影响，探讨其抗血栓形成作用的血液流变学机制。方法：大鼠ｓｃ角叉菜胶５ｍｇ·ｋｇ－１复制血栓模型。给药后观察大鼠尾部血栓形成状况，进行血液流变学分析。结果：ＭＮ９２０２０．１、１、１０μｍｏｌ·ｋｇ－１能对抗角叉菜胶引起的大鼠血栓黑尾的形成（Ｐ＜０．０５，Ｐ＜０．０１），呈现出明显的剂量依赖关系（ｒ＝０．９９９５）；０．０１，０．１，１，１０μｍｏｌ·ｋｇ－１能降低ＲＢＣ聚集指数（Ｐ＜０．０５，Ｐ＜０．０１），增强ＲＢＣ变形性（Ｐ＜０．０５，Ｐ＜０．０１），但不改变ＲＢＣ电泳迁移率；大剂量的ＭＮ９２０２１，１０μｍｏｌ·ｋｇ－１能降低切变率为１５０·ｓ－１、５０·ｓ－１、１·ｓ－１时全血粘度。结论：ＭＮ９２０２具有对抗角叉菜胶引起的大鼠血栓形成作用。其作用可能与其改善血液流变性特征有关。     

贝那普利与美托洛尔合用对大鼠肾性高血压的治疗作用

目的观察贝那普利（Ｂｅｎ）与美托洛尔（Ｍｅｔ）合用８ｗｋ、１６ｗｋ对高血压大鼠动脉收缩压（ＳＢＰ）、左心室肥厚和心肌纤维化的作用。方法采用两肾一夹Ｇｏｌｄｂｌａｔ高血压模型;尾容积法测定清醒大鼠动脉收缩压;以左心室羟脯氨酸含量反映心肌纤维化程度。结果肾动脉术后１２和２０ｗｋ时模型组ＳＢＰ,左心室重与体重之比（ＬＶＷ／ＢＷ）和左心室胶原蛋白含量（ＬＶＣＣ）均高于假手术组;２０ｗｋ时该３项指标的净增值分别为：ΔＳＢＰ为１２６,ΔＬＶＷ／ＢＷ为１３１,ΔＬＶＣＣ为３８。与模型组比,术后１２ｗｋＢｅｎ１５ｍｇ·ｋｇ－１·ｄ－１,ｉｇ＋Ｍｅｔ１０ｍｇ·ｋｇ－１·ｄ－１,ｉｇ联合用药组的ΔＳＢＰ,ΔＬＶＷ／ＢＷ,ΔＬＶＣＣ分别下降了７８％、８０％和７８％;术后２０ｗｋ时,上述指标分别下降８７％、９２％和９０％;且低于两个单用药组。结论Ｂｅｎ和Ｍｅｔ在抑制高血压大鼠及心肌纤维化方面有协同作用,这种作用随治疗时间的延长而明显。     

去甲乌药碱的药理作用与心脏β－AR关系的初步研究

附子有效成分去甲乌药碱（ＤＭＣ）的药理作用以及与肾上腺素能β受体（β－ＡＲ）的关系的研究表明，０．５ｍｇ·ｋｇ－１的ＤＭＣ可使正常小鼠心肌β－ＡＲ轻度上调，与异丙肾上腺素（ＩＳＯ）相比，ＤＭＣ能轻度激动ｃＡＭＰ，使其血浆含量升高，升高的峰值时间在１０ｍｉｎ左右。ＤＭＣ的最小激动量为０．５ｍｇ·ｋｇ－１，最大激动量为５ｍｇ·ｋｇ－１。ＤＭＣ对１２５Ｉ－ＰＩＮ的竞争抑制实验表明，在１×１０－６～１×１０－５ｍｏｌ·Ｌ－１时，ＤＭＣ可抑制１２５Ｉ－ＰＩＮ与β－ＡＲ结合，与心得安比较抑制浓度大４～５个数量级。与ＩＳＯ合并用药观察血浆ｃＡＭＰ浓度变化提示，０．５ｍｇ·ｋｇ－１ＤＭＣ与小剂量（０．１ｍｇ·ｋｇ－１）和较大剂量（１ｍｇ·ｋｇ－１）的ＩＳＯ合用时，既无协同作用，也未见拮抗作用。     

牛磺酸与硫酸镁联合用药的研究──Ⅰ、抗实验性缺血／再灌心律失常作用

采用麻醉大鼠缺血／再灌心律失常模型，研究牛磺酸（Ｔａｕｒ）和硫酸镁（ＭｇＳＯ４）单用及合用的抗再灌心律失常作用，并观察对正常大鼠在体血流动力学的影响。结果表明：Ｔａｕｒ５０ｍｇ·ｋｇ－１，ＭｇＳＯ４２５ｍｇ·ｋｇ－１具有部分抗心律失常作用；Ｔａｕｒ１００、１５０ｍｇ·ｋｇ－１，ＭｇＳＯ４５０、１００ｍｇ·ｋｇ－１抗心律失常疗效增加；两药小剂量合用，作用较各单用药组明显增强。ＭｇＳＯ４２５ｍｇ·ｋｇ－１对大鼠心肌仅有轻度负性肌力作用，与Ｔａｕｒ５０ｍｇ·ｋｇ－１合用，负性肌力未见增加，但具有负性频率和减低心肌耗氧量作用，提示其抗心律失常作用与保护心肌有一定关系。     

褪黑素抗自由基作用及其机制

目的研究褪黑素（ＭＥＬ）的抗自由基作用,并探讨其作用机制。方法以丙二醛（ＭＤＡ）为指标,考察ＭＥＬ对四氯化碳（ＣＣｌ４）或氰化钾（ＫＣＮ）处理小鼠肝或脑组织脂质的保护作用;考察ＭＥＬ对环磷酰胺所致小鼠骨髓细胞微核的影响;观察ＭＥＬ清除羟自由基（·ＯＨ）作用,及对醋氨酚处理小鼠肝谷胱甘肽（ＧＳＨ）含量和大鼠红细胞超氧化物歧化酶（ＳＯＤ）、过氧化氢酶（ＣＡＴ）和全血谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）的影响。结果ＭＥＬ（２．０,１０．０ｍｇ·ｋｇ－１,ｉｐ）能显著对抗ＣＣｌ４或ＫＣＮ所致小鼠肝脏或脑组织丙二醛含量的增加。ＭＥＬ（１０．０ｍｇ·ｋｇ－１,ｉｐ）可明显抑制环磷酰胺引起的小鼠骨髓细胞微核增多。ＭＥＬ（０．０７８～５．０ｍｍｏｌ·Ｌ－１）可直接清除·ＯＨ。ＭＥＬ（１．０,１０．０ｍｇ·ｋｇ－１,ｉｐ）可显著对抗醋氨酚（ＡＡＰ）所致小鼠ＧＳＨ的耗竭作用。ＭＥＬ（１．０,５．０ｍｇ·ｋｇ－１,ｉｐ）亦可显著提高大鼠红细胞内ＳＯＤ、ＣＡＴ、全血ＧＳＨ－Ｐｘ活性。结论ＭＥＬ可保护脂质和核酸免受过氧化损伤,这可能与其直接清除·ＯＨ,提高机体ＧＳＨ含量及增强ＳＯＤ、ＣＡＴ、ＧＳＨ－Ｐｘ活力有关。     

白芍总甙对大鼠腹腔巨噬细胞产生肿瘤坏死因子的影响

采用Ｌ９２９细胞株细胞毒检测法，观察了白芍总甙（ＴＧＰ）对ＬＰＳ诱导大鼠腹腔巨噬细胞（ＭΦ）产主肿瘤坏死因子（ＴＮＦ）的影响。结果表明、亚适量ＬＰＳ（５ｍｇ·Ｌ－１）诱导大鼠腹腔ＭΦ培养上清在６ｈ对Ｌ９２９细胞杀伤百分率最大．ＴＧＰ（２．５ｍｇ·Ｌ－１）能促进ＬＰＳ诱导大鼠腹腔ＭＯ产生ＴＮＦ，但不改变其动力学过程。ＴＧＰ（０．５～２５０ｍｇ·Ｌ－１）对ＬＰＳ诱导ＭΦ产生ＴＮＦ量效曲线呈钟罩形．提示ＴＧＰ对ＭΦ产主ＴＮＦ具有浓度依赖性双向调节作用。不同浓度ＴＧＰ对Ｌ９２９细胞无直接杀伤作用，亦无ｒｈＴＮＦ－α拮抗作用。     

地黄低聚糖对快速老化模型小鼠造血功能的影响

目的：研究地黄低聚糖（ＲＧＯＳ）对快速老化模型小鼠（ＳＡＭＰ８）造血功能的影响。方法：采用造血祖细胞体外克隆培养等实验血液学方法。结果：ＲＧＯＳ１０，２０ｍｇ·ｋｇ－１可使ＳＡＭＰ８小鼠的ＣＦＵ－Ｓ、ＣＦＵ－ＧＭ、ＣＦＵ－Ｅ和ＢＦＵ－Ｅ明显增多，并可使外周血中降低的ＷＢＣ数明显增加。提示ＲＧＯＳ可刺激ＳＡＭＰ８小鼠造血干细胞、祖细胞的增殖分化。集落刺激活性实验显示ＲＧＯＳ可使小鼠体内的集落刺激因子产生明显增多。小鼠骨髓组织学研究结果也进一步证实了ＲＧＯＳ增强ＳＡＭＰ８小鼠造血功能的作用。结论：ＲＧＯＳ可以增强ＳＡＭＰ８小鼠的造血功能。     

实验性结肠炎中氧化过度及褪黑素的保护作用

目的　探讨褪黑素对大鼠免疫性结肠炎的影响及有关机制。方法　应用三硝基苯磺酸和乙醇制备大鼠免疫性结肠炎模型。实验设正常对照组、模型对照组、阳性药物对照组 (5 氨基水杨酸 ,1 0 0mg·kg- 1 )、褪黑素给药组 (2 5 ,5 0 ,1 0 0mg·kg- 1 ) ,每天灌肠给药 1次 ,给药时间从制备模型 1wk后开始至实验结束共 3wk。观察大鼠结肠黏膜损伤指数 (CMDI)、粪便隐血实验 (OB)、髓过氧化物酶 (MPO)含量和黏膜病理组织学 (HS)情况 ,并检测结肠组织丙二醛(MDA)、谷胱甘肽过氧化物酶 (GSHPx)、过氧化氢酶(CAT)、超氧化物歧化酶 (SOD)、血浆和结肠组织一氧化氮(NO)含量。结果　模型组大鼠结肠CMDI、HS、OB程度和MPO水平均比正常组升高 ,褪黑素可改善结肠炎大鼠CM DI和HS ,降低MPO水平和粪便OB程度 ,改善结肠黏膜病理损伤 ,大鼠结肠MDA、血浆和结肠NO含量增加 ,结肠SOD、GSHPx和CAT水平降低 ,MT可降低MDA、NO含量 ,增加GSHPx、SOD和CAT水平。结论　MT对大鼠结肠黏膜损伤具有保护作用     

具备高同型半胱氨酸血症的实验性结肠炎模型的建立

目的建立具备高同型半胱氨酸血症(HHcy)的实验性结肠炎模型,初步探讨Hcy对结肠炎症损伤的影响。方法将SD大鼠分为4组:正常对照组(NS灌肠+皮下注射NS)、正常对照+Hcy注射组(NS灌肠+皮下注射Hcy)、TN-BS模型对照组(TNBS/乙醇灌肠+皮下注射NS)、TNBS模型+Hcy注射组(TNBS/乙醇灌肠+皮下注射Hcy)。以TN-BS/乙醇混合溶液(100 mg·kg-1TNBS加入等体积NS)灌肠1次制备结肠炎模型后,采用皮下注射同型半胱氨酸(0.03μmol·kg-1,每天2次,间隔8 h,连续30 d)造成HHcy模型。实验结束后通过高效液相荧光法(HPLC-FD)检测血浆和结肠粘膜Hcy水平,进行DAI评分并取结肠组织进行HE染色评分,结肠组织匀浆检测MPO活性。结果与正常对照组比较,TNBS模型对照组大鼠DAI和HI评分增高(P<0.01),结肠组织MPO活性增高(P<0.01)。与TNBS模型对照组比较,TNBS模型+Hcy注射组大鼠血浆和结肠粘膜Hcy水平明显增高(P<0.01),DAI和HI评分明显增高(P<0.01),结肠组织MPO活性明显增高(P<0.01)。结论皮下注射同型半胱氨酸可以建立具备高同型半胱氨酸血症的实验性结肠炎模型,可用于探讨Hcy在结肠炎中的作用机制。     

1,8-cineole (eucalyptol), a monoterpene oxide attenuates the colonic damage in rats on acute TNBS-colitis.

The monoterpene oxide, 1,8-cineole (cineole, eucalyptol) was examined for its possible influence on the acute phase of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. The test compound, 1,8-cineole (200 and 400 mg/kg) or vehicle (1 ml, 2% Tween 80) was instilled rectally, 24, and 2 h before (pre-treatment) or 2 and 24 h after (post-treatment) the induction of colitis by intracolonic administration of TNBS (0.25 ml of 25 mg of TNBS in 50% ethanol). Rats were killed 48 h after colitis induction and colonic segments were analysed for gross damage scores, changes in wet weights, myeloperoxidase activity, an indicator of neutrophilic infiltration and glutathione level, a major cellular antioxidant. TNBS induced an extensive inflammation and ulceration in the colon. Colonic damage was associated with an increase in myeloperoxidase activity and by a decrease in glutathione. When compared to vehicle-treated TNBS controls, a marked reduction in gross damage scores and wet weights (mg/cm) of colonic segments were evident in animals pre-treated but not post-treated with 1,8-cineole. Cineole also significantly reduced the myeloperoxidase activity, and caused repletion of glutathione. These results confirm the anti-inflammatory action of 1,8-cineole and suggest its potential value as a dietary flavoring agent in the prevention of gastrointestinal inflammation and ulceration.     

Protective effect of taurohyodeoxycholic acid from Pulvis Fellis Suis on trinitrobenzene sulfonic acid induced ulcerative colitis in mice

Ulcerative colitis is a nonspecific inflammatory disorder characterized by oxidative and nitrosative stress, leucocyte infiltration and up-regulation of pro-inflammatory cytokines. The aim of this study is to evaluate the effect of taurohyodeoxycholic acid (THDCA) isolated from Pulvis Fellis Suis on acute ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS) in mice. The efficacy of THDCA was studied by macroscopical and histological scoring systems as well as myeloperoxidase (MPO) activity. Serum levels, including tumor necrosis factor (TNF)-α and interleukin (IL)-6 were assayed by enzyme-linked immunoassay. The expression of cyclooxygenase (COX)-2 in the colons was assessed by immunohistochemical analysis. Treatment with THDCA in doses of 25, 50 and 100 mg/kg/day and sulfasalazine in a dose of 500 mg/kg/day used as reference for 7 consecutive days after the induction of colitis, significantly decreased colonic MPO activity, TNF-α, IL-6 serum levels and the expression of COX-2 in colon compared with TNBS induced ulcerative colitis model group. Moreover, THDCA attenuated the macroscopic colonic damage and the histopathological changes induced by TNBS. All the effects of these parameters were comparable to that of the standard sulfasalazine, especially at the highest dose level. The results suggested that THDCA from Pulvis Fellis Suis has a protective effect in TNBS-induced ulcerative colitis which might be due to its anti-inflammatory activities, and that it may have therapeutic value in the setting of inflammatory bowel disease.     

MT对大鼠乙酸性结肠炎的影响及有关机制初探

目的　探讨褪黑素对大鼠乙酸性结肠炎的影响及有关机制。方法　制备大鼠乙酸性结肠炎模型 ,实验设正常对照组、模型对照组、阳性药物对照组 (5 氨基水杨酸 ,10 0mg·kg-1)、MT给药组 (2 5 ,5 0 ,10 0mg·kg-1) ,采用灌肠方式给药 ,每天 1次 ,给药时间从制备模型 2 4h后开始至实验结束共 7d ,正常及模型对照组均给予生理盐水灌肠。实验结束后观察大鼠结肠粘膜损伤指数 (CMDI)、粪便隐血实验(OB)、髓过氧化物酶 (MPO)含量和粘膜病理组织学 (HS)情况 ,并检测结肠组织丙二醛 (MDA)、谷胱甘肽过氧化物酶(GSH Px)、过氧化氢酶 (CAT)、超氧化物歧化酶 (SOD)、一氧化氮 (NO)含量。结果　乙酸性结肠炎大鼠结肠CMDI、HS、OB程度和MPO水平均比正常组明显升高 ,MT灌肠可减轻乙酸性结肠炎大鼠的CMDI和粪便OB程度 ,降低MPO水平 ,10 0mg·kg-1MT可改善结肠粘膜病理损伤。同时可见模型组大鼠结肠组织MDA、NO含量增加 ,SOD、GSH Px和CAT水平降低。MT可明显降低MDA、NO含量 ,增加GSH Px、SOD和CAT水平。结论　MT对乙酸性结肠炎大鼠结肠粘膜损伤具有保护作用     

Protective effect of taurine on TNBS-induced inflammatory bowel disease in rats

We had previously reported that the protective effect of taurine against indomethacin-induced gastric mucosal injury was due to its antioxidant effects, which inhibited lipid peroxidation and neutrophil activation. In this study, we examined the effect of taurine on reducing the inflammatory parameters of trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease (IBD), in rats. In order to induce IBD, ethanolic TNBS was given to rats intracolonically. Then they received 500 mg/kg/day of taurine orally and were sacrificed one week after IBD induction. While ulceration and inflammation of distal colon with formation of granuloma in the vehicle-treated IBD rats two days after administration of TNBS were observed, treatment with taurine ameliorated colonic damage and decreased the incidence of diarrhea and adhesion. Also, colon weight as an index of tissue edema, which was markedly increased in the IBD rats, became significantly lower after taurine treatment. Myeloperoxidase (MPO) activity in the vehicle-treated IBD rats was substantially increased, compared with that of normal control. The taurine-treated animals significantly reduced MPO activity (35% lower) when compared with that of the vehicle-treated animals. Taurine treatment decreased both basal and formyl-methionyl leucyl phenylalanine-stimulated reactive oxygen generation from colonic tissue in the IBD rats. These results suggest that the administration of taurine reduce the inflammatory parameters in this IBD rat model by increasing defending capacity against oxidative damage.     

Modulation by heme and zinc protoporphyrin of colonic heme oxygenase-1 and experimental inflammatory bowel disease in the rat

Reactive oxygen species, suggested to be involved in inflammatory bowel disease, may be modulated by endogenous anti-oxidant products of heme oxygenase-1 (HO-1). In the present work, HO-1 expression in trinitrobenzene sulphonic acid (TNBS)-induced colitis in the rat and the effects of HO-1 modulation, particularly by the HO-1 inducer, heme, were further evaluated. Colitis was induced by intracolonic challenge with TNBS and assessed macroscopically and by myeloperoxidase (MPO) assay. Heme oxygenase activity was determined by measurement of bilirubin formation and HO-1 protein expression was determined by Western blotting. TNBS challenge led to an early and substantial induction of HO-1 protein expression and heme oxygenase activity in the colon that peaked after 48-72 h and declined over 10 days. Heme (30 micromol/kg/day, s.c) increased colonic HO-1 protein expression and enzyme activity and decreased colonic damage and myeloperoxidase activity. Short-term administration of cadmium chloride (2 mg/kg, s.c.), another known HO-1 inducer, also reduced the colonic injury and myeloperoxidase levels. In contrast, the HO-1 inhibitor, zinc protoporphyrin (50 micromol/kg/day, s.c) significantly increased the colonic damage and myeloperoxidase activity over 10 days, as did tin protoporphyrin (30 micromol/kg/day, s.c). These results support the proposal that induction of HO-1 provides a protective mechanism in this model under both acute and more-chronic conditions, and that its selective up-regulation could thus be of therapeutic potential in colitis.     

龙胆苦苷对结肠炎小鼠的治疗作用

目的探究龙胆苦苷对结肠炎小鼠的治疗作用。方法采用2,4,6-三硝基苯磺酸(TNBS)-乙醇溶液诱导结肠炎小鼠模型,测定龙胆苦苷给药后对小鼠体质量、结肠指数、胸腺质量、结肠组织中髓过氧化物酶(MPO)活性以及血清炎症细胞因子TNF-α和IL-8的影响,并通过免疫组化法观察龙胆苦苷对小鼠结肠组织中环氧合酶-2(COX-2)蛋白表达的影响。结果给药1周后,龙胆苦苷各剂量组小鼠体质量与模型组相比显著改善;小鼠结肠指数、结肠组织中MPO活性以及炎性细胞因子TNF-α和IL-8与模型组相比均显著降低(P<0.05);免疫组化结果显示,龙胆苦苷能降低结肠炎小鼠组织中环氧合酶-2(COX-2)的蛋白表达。结论龙胆苦苷能修复TNBS-乙醇溶液诱导的小鼠结肠损伤,对小鼠结肠炎有显著的治疗作用。     

The effect of heparin on trinitrobenzene sulphonic acid-induced colitis in the rat

Background:

Reduced blood coagulability seems to protect against inflammatory bowel disease; pilot studies using heparin in patients with inflammatory bowel disease have reported positive results.

Aim:

To evaluate the effects of heparin treatment on microangiographic and on inflammatory parameters in experimental colitis, induced by trinitrobenzene sulphonic acid (TNBS)-ethanol.

Methods:

Four groups of rats: (i) controls (saline enema), TNBS-induced colitis with (ii) sham treatment (saline, s.c.), (iii) dexamethasone (0.25 mg/kg/day s.c.) and (iv) heparin (500 U/kg t.d.s., s.c.). Microangiography was performed 2 and 4 days after colitis induction. Partial thromboplastin time, colonic wet weight, macroscopic damage score and mucosal myeloperoxidase (MPO) activity were determined at day 4.

Results:

TNBS-induced colitis caused a reduction in visible bowel wall vessels, which was prevented by heparin (P < 0.05) but not by steroids. The macroscopic damage scores and colon wet weights were similar in all colitis groups. Compared to untreated colitis the MPO activity in heparin-treated animals was of borderline significance.

Conclusions:

Heparin treatment improved microangiographic features and reduced inflammation to a certain degree. Steroids delayed development of colon hypoperfusion, but were ineffective on MPO activity. It remains to be determined if the observed effects are due to the antithrombotic activity of heparin or to an anti-inflammatory action.

     

Effect of intracolonic benzalkonium chloride on trinitrobenzene sulphonic acid-induced colitis in the rat

Background:

We investigated the effects of benzalkonium chloride (BAC) on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats.

Methods:

TNBS was administered intrarectally before and/or after BAC treatment. In the first study, the effects of treatment with BAC 6, 12 or 24 h after TNBS were examined. In the second study, animals were treated with BAC before, after or before and after TNBS, and were examined 7 days later. The severity of colitis was assessed by macroscopic and histological scoring of the colonic damage and by determination of colonic myeloperoxidase (MPO) activity. Macrophages and CD4⁺ and CD8⁺ T cells were examined by immuno-histochemistry.

Results:

When BAC was instilled into the colon 6, 12 or 24 h after TNBS, weight loss and macroscopic and histological features of the colon were similar to that of controls (TNBS alone). In contrast, MPO activity was significantly reduced in all three groups post-treated with BAC. In the groups examined 7 days after TNBS treatment, rats post-treated with BAC exhibited increased weight gain and significantly reduced macroscopic damage and MPO activity compared to the TNBS control group. Rats pre-treated with BAC exhibited less macroscopic damage of the colon than rats receiving only TNBS, but histological damage, MPO and weight gain were unchanged from TNBS controls. Immunohistochemistry revealed that BAC pre-treatment increased the numbers of macrophages and T cells in the colon. After TNBS treatment, macrophage accumulation was evident in the colon, but T cells were scarce. However, these cells were preserved or enhanced in the colonic mucosa in TNBS-treated rats that had been pre-treated with BAC.

Conclusions:

Treatment with BAC, particularly after induction of colitis, produces a significant reduction in the severity of tissue injury and inflammation through mechanisms that are not fully understood.