褪黑素对结肠炎大鼠结肠内一氧化氮合酶和环氧合酶-2含量的影响

目的 研究褪黑素对大鼠结肠炎的抗炎作用是否与诱生性一氧化氮合酶（iNOS）和环氧合酶-2(COX-2)有关。方法 制备大鼠乙酸性结肠炎和2,4,6-三硝基苯磺酸(TNBS)结肠炎模型。实验设正常对照组，模型对照组，5-氨基水杨酸对照组（100 mg·kg^-1），褪黑素组（2.5，5.0，10.0 mg·kg^-1），每天灌肠给药一次（乙酸模型给7 d, TNBS模型给21 d）。检测大鼠结肠一氧化氮(NO)，前列腺素（PG）E₂，iNOS和COX-2含量。结果 模型组大鼠结肠粘膜损伤明显，NO，PGE₂，iNOS和COX-2含量显著增加。褪黑素可减轻大鼠结肠损伤，明显抑制NO，PGE₂合成并减少iNOS，COX-2含量。结论 大鼠结肠经TNBS和乙酸致炎后iNOS，COX-2，NO及PGE₂合成增强，褪黑素通过抑制iNOS和COX 2表达减轻结肠损伤。     

阿魏酸钠对结肠炎大鼠结肠组织一氧化氮合酶和环氧合酶的影响

目的　研究阿魏酸钠 (SF)对大鼠结肠炎的抗炎保护作用及其机制。方法　建立大鼠乙酸性结肠炎模型。SF与5 氨基水杨酸灌肠给药 1wk后评价大鼠结肠黏膜损伤指数(CMDI) ,采用试剂盒及免疫组化方法检测结肠组织NO、MPO、PGE2 含量及结构型一氧化氮合酶 (cNOS) ,诱生型一氧化氮合酶 (iNOS) ,环氧合酶 1(COX 1) ,环氧合酶 2 (COX 2 )和核因子 κBp6 5 (NF κBp6 5 )的表达水平。 结果　SF(2 0 0、4 0 0、80 0mg·kg-1)灌肠用药均降低模型组大鼠升高的CMDI及结肠组织NO、MPO、PGE2 含量 ,下调iNOS、COX 2、NF κBp6 5的过度表达 ,亦抑制cNOS的正常表达水平 ,对COX 1表达影响不明显。SF用药呈现一定量效关系。结论　SF为一氧化氮合酶及部分选择性COX 2抑制剂 ,对大鼠结肠炎具有一定抗炎保护作用。     

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     

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     

灵芝多糖肽对小鼠腹腔巨噬细胞一氧化氮产生的影响

目的　研究灵芝多糖肽 (GLPP)对小鼠腹腔巨噬细胞一氧化氮产生的影响并探讨其作用机制。方法　以Griess法 ,观察GLPP对LPS诱导小鼠腹腔巨噬细胞一氧化氮(NO)产生的影响 ;以免疫组化法检测诱导型一氧化氮合成酶 (iNOS)的表达 ,观察GLPP对iNOS的影响。结果　GLPP(2 5～ 2 0 0mg·kg-1)灌胃给药 5d或体外给药 (3 12 5～ 2 0 0mg·L-1)均可促进巨噬细胞NO释放 ,但对LPS刺激NO的释放影响不大 ;GLPP(10 0mg·kg-1)灌胃给药 5d或体外给药 (10mg·L-1)均可使巨噬细胞iNOS含量增加。结论　GLPP可增加小鼠腹腔巨噬细胞NO产生 ,其机制可能与其促进巨噬细胞iNOS合成有关。     

侧柏总黄酮的抗炎作用

目的研究侧柏总黄酮的抗炎作用。方法以二甲苯致小鼠耳肿胀及角叉菜胶诱发大鼠足爪肿胀模型分别探讨侧柏总黄酮对小鼠耳片肿胀及大鼠足爪肿胀的抑制作用。测定大鼠足爪组织中一氧化氮 (NO)及前列腺素E2 (PGE2 )的含量。结果侧柏总黄酮在 12 5～ 5 0 0mg·kg-1内呈剂量依赖地抑制二甲苯诱导的小鼠耳肿胀 ,2 5 0mg·kg-1剂量能显著抑制大鼠足爪肿胀 ,其作用强于2 0mg·kg-1的地塞米松。侧柏总黄酮能抑制大鼠炎症足爪组织NO及PGE2 的生物合成。结论侧柏总黄酮具有较强的抗炎作用 ,其抗炎作用可能与抑制NO及PGE2 的生物合成或释放有关。     

兰索拉唑对乙醇诱导大鼠胃黏膜损伤的保护作用及其机制

目的　研究兰索拉唑 (LP)对乙醇诱导大鼠胃黏膜损伤的保护作用 ,探讨胃泌素受体和环氧化酶 2 (COX 2 )表达在此过程中的作用。方法　大鼠ig给予LP 0 5、5、5 0mg·kg-1·d-1,或ig联合给予LP 5 0mg·kg-1·d-1和胃泌素受体拮抗剂AG 0 4 1R 3、10、30mg·kg-1·d-1,对照组ig给予羧甲基纤维素 (CMC) 2 5mg·kg-1·d-1,连续 14d。末次给药后 8h各组大鼠ig给予无水乙醇 1ml,观察胃损伤指数 (LI)及光镜下的胃黏膜病理学改变。酶免疫方法测定胃黏膜前列腺素E2 (PGE2 )水平 ,WesternBlot和免疫组化检测胃黏膜COX 2表达。评价特异性COX 2抑制剂NS 398对LP诱导的PGE2 合成及胃黏膜保护作用的影响。结果　在 0 5、5、5 0mg·kg-1LP组 ,LI分别为 (2 5 3± 0 33) %、(1 84±0 2 9) %和 (0 83± 0 12 ) % ,小于对照组 (3 6 5± 0 19) % (P<0 0 5 ) ;胃黏膜PGE2 含量分别为 (42 7± 32 ) ,(483± 12 1)和 (6 14± 82 ) pg·g-1wwt ,高于对照组 (2 6 6± 81) pg·g-1wwt(P <0 0 5 )。LP剂量依赖性地增加大鼠胃黏膜COX 2表达。然而 ,同时给予AG 0 4 1R阻断了LP诱导的胃黏膜保护作用、COX 2表达和PGE2 合成。NS 398抑制LP诱导的PGE2 合成及胃黏膜保护作用。结论　LP的胃黏膜保护作用与内源性胃泌素激活胃泌素受     

质子泵抑制剂的胃黏膜保护作用与环氧化酶-2表达

目的　探讨质子泵抑制剂 (PPIs)的胃黏膜保护作用与环氧化酶 2 (COX 2 )表达的关系。方法　♂SD大鼠ig给予雷巴拉唑、奥美拉唑或兰索拉唑 5 0mg·kg-1·d-1,对照组ig给予质量分数为 0 5 %羧基纤维素 5ml·kg-1·d-1,连续 2wk。Westernblot和免疫组化检测胃黏膜COX 2表达。酶免疫方法测定胃黏膜中前列腺素E2 (PGE2 )水平 ,评价兰索拉唑和特异性COX 2抑制剂NS 3 98对乙醇所致大鼠胃黏膜损伤的影响。结果　 3种PPI均增加大鼠胃黏膜COX 2的表达。兰索拉唑呈剂量依赖性地增加胃黏膜中PGE2 含量 ,有效地减轻乙醇对胃黏膜的损伤作用。NS 3 98有效地阻断了兰索拉唑诱导的PGE2 合成及胃黏膜保护作用。结论　PPIs通过诱导胃黏膜COX 2表达 ,增加PGE2 合成而发挥胃黏膜保护作用     

褪黑激素调节巨噬细胞功能减轻结肠免疫损伤

目的:研究褪黑素(MT)对大鼠结肠免疫损伤的影响及与巨噬细胞功能的关系.方法:利用2,4,6-三硝基苯磺酸(TNBS)和乙醇灌肠制备大鼠结肠炎模型.实验设正常对照组、模型对照组、5-氨基水杨酸给药组(100 mg/kg)和MT给药组(2.5,5.0,10.0 mg/kg),每大灌肠给药一次,从制备模型d 7开始共21 d.测定结肠粘膜损伤指数(CMDI)、粘膜病理组织学评分(HS)、粪便隐血实验(OBT)和髓过氧化物酶(MPO)、IL-1、TNF-α、NO水平.结果:大鼠经TNBS和乙醇处理后CMDI、HS、OBT和MPO水平以及结肠和血浆中IL-1、TNF-α和NO水平明显高于正常,MT可不同程度逆转上述变化,减轻大鼠结肠免疫损伤.结论:MT灌肠能减轻结肠炎大鼠粘膜损伤,此与MT调节巨噬细胞功能有关.     

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。     

Influence of simultaneous inhibition of cyclooxygenase-2 and inducible nitric oxide synthase in experimental colitis in rats

The inflamed mucosa in ulcerative colitis produces high amount of prostaglandin (PG) and nitric oxide (NO) through inducible enzymes: cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), respectively, implicating them as potential anti-inflammatory drug targets. COX-2 or iNOS-related treatments in different models of colitis have yielded ambiguous results ranging from exacerbation of disease to abolition of inflammation. iNOS and COX-2 induction is blocked by potent anti-inflammatory glucocorticoids, however, serious side effects including relapses limit their usefulness in colitis for long time. Simultaneous inhibition of iNOS and COX-2 was investigated in the current study in 2, 4, 6 trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Treatment group received rofecoxib, aminoguanidine hydrochloride or their combination at different doses at 48, 36, 24, 12 and 1 h prior to induction of colitis and 12 h later. Colonic myeloperoxidase (MPO), COX-2, nitrate and nitrite, tumor necrosis factor-α (TNF-α) and lipid peroxidation were maximally reduced by combination of 10 mg/kg rofecoxib and 30 mg/kg of aminoguanidine hydrochloride in TNBS-induced colitis in rats. However, maximum increase in SOD and catalase was noted by this combination. Rats treated with rofecoxib, aminoguanidine hydrochloride and their combinations reduced the inflammation, acute colonic damage produced by TNBS as verified by macroscopic changes in colon. Combination of rofecoxib (10 mg/kg) and aminoguanidine hydrochloride (30 mg/kg) has maximal protective effect on colonic injury induced by TNBS enema which is probably, via mechanism of local inhibition of iNOS and COX-2 activity in colonic mucosa and support the idea that simultaneous inhibition of iNOS and COX-2 inhibitors have a promising potential in the treatment of colitis.     

Vascular contribution of adrenomedullin to microcirculatory improvement in experimental colitis

The effect of adrenomedullin (AM), a peptide that has demonstrated vasodilatory activity, was studied in the colon and small mesenteric arteries of rats in a chronic model of inflammatory bowel disease. AM (50 ng/kg/day) was administered i.p. daily, starting 24h after trinitrobenzensulfonic acid (TNBS, 30 mg) instillation. After 14 days, rats were sacrificed, colons were macroscopically analyzed and biochemical parameters (myeloperoxidase activity, cytokines, cyclooxygenase-2 (COX-2) as well as inducible nitric oxide synthase (iNOS) expression) were determined. Vascular function of small mesenteric arteries was assessed by addition of phenylephrine (10?? to 10?? mol/L) and participation of COX and NOS pathways was also evaluated by using different inhibitors: indomethacin, NS-398, L-NNA, and 1400 w. Chronic AM treatment significantly reduced colonic macroscopic damage and inflammation markers. TNBS instillation induced COX-2 and iNOS expressions in colon and small mesenteric arteries; AM treatment decreased COX-2 expression only in microvessels from rats with colitis. An attenuation of phenylephrine-induced contraction was detected in small mesenteric arteries from both TNBS and AM-treated rats. COX and NOS inhibitors altered the contractile ability of phenylephrine in small mesenteric arteries from TNBS rats, suggesting the involvement of COX-2 and iNOS derived factors in the deleterious effect of TNBS on vascular reactivity; AM administration was able to reduce such alteration. Finally, treatment with the peptide significantly reduced colonic nitric oxide (NO) levels, without affecting plasma concentration. In conclusion, AM showed beneficial effects in the restoration of vascular function through the regulation of vasoactive products derived from COX-2 and iNOS.     

康复新液缓解乙酸诱导大鼠急性溃疡性结肠炎及机制研究

目的 研究康复新液对乙酸诱导大鼠急性溃疡性结肠炎（ulcerative colitis,UC）细胞因子的影响,并初步探讨其作用机制。方法 采用乙酸灌肠建立急性UC大鼠模型,除正常对照组及模型对照组外,其余各组分别灌肠给予结肠宁、康复新液2.50,1.25,0.625 g·kg^-1,测定疾病活动指数（disease activity index,DAI）、结肠黏膜损伤指数（colon mucosa damage index,CMDI）及病理组织学评分（histopathological score,HS）,采用酶联免疫吸附法检测大鼠血清中白介素-6（interleukin-6,IL-6）、C反应蛋白（C-reactive protein,CRP）、一氧化氮合酶（nitric oxide synthase,iNOS）以及结肠组织中表皮生长因子（epidermal growth factor,EGF）、环氧合酶-2（cyclooxygenase-2,COX-2）、髓过氧化物酶（myeloperoxidase,MPO）、iNOS的含量。结果 与模型对照组相比,结肠宁及康复新液高剂量能显著降低UC大鼠IL-6、CRP、iNOS、COX-2、MPO表达,升高EGF的表达水平（P<0.01）,改善组织病变情况。结论 康复新液对乙酸诱导的UC有治疗作用,作用机制可能与下调大鼠体内炎症因子的表达量,上调EGF的表达量有关。     

Ameliorative effects of 3,4-oxo-isopropylidene-shikimic acid on experimental colitis and their mechanisms in rats

The aim of the present study was to investigate the therapeutic effect and mechanism of 3,4-oxo-isopropylidene-shikimic acid (ISA) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. (50, 100, 200 mg/kg) was administered for 14 days, 1 day after the induction of colitis by TNBS. The colonic injury and inflammation were assessed by macroscopic damage scores and myeloperoxidase (MPO) activity. Malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in plasma were measured with biochemical methods. Prostaglandin E₂ (PGE₂) level in colon was determined by radioimmunoassay. Expressions of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), inhibitor kappa B-alpha (IκBα) and nuclear factor kappa B (NF-κB) p65 proteins in the colonic tissue were detected with immunohistochemistry. Enhanced colonic mucosal injury, inflammatory response and oxidative stress were observed in the animals clystered with TNBS, which was manifested as the significant increase in colon mucosal damage index, MPO activity, levels of MDA, NO and PGE₂, as well as the expressions of iNOS, COX-2 and NF-κB p65 proteins in the colonic mucosa, and the significant decrease in expressions of IκBα proteins in the colonic mucosa. However, these parameters were found to be significantly ameliorated in rats treated with ISA at given doses, especially at 100 mg/kg and 200 mg/kg. Administration of ISA may have significant therapeutic effects on experimental colitis in rats, probably due to its mechanism of antioxidation, its inhibition of arachidonic acid metabolism and its modulation of the IκBα/NF-κB p65 expression.     

葡萄籽原花青素对复发性结肠炎大鼠血清抗氧化能力及NO含量的影响

目的：观察葡萄籽原花青素（GSPE）对复发性结肠炎大鼠血清抗氧化能力及NO含量的影响,初步探讨葡萄籽原花青素治疗复发性结肠炎的作用机制。方法：直肠给予雄性Wistar大鼠80mg/kg2,4,6-三硝基苯磺酸（TNBS）/50%乙醇溶液复制结肠炎模型,在第16天时,用30mg/kgTNBS/50%乙醇溶液诱导结肠炎复发的模型。大鼠第二次致炎24h后,分别应用GSPE低、中、高剂量（100、200、400mg/kg）灌胃对其进行治疗,并以柳氮磺吡啶（SASP,500mg/kg）作为阳性对照。连续给药7d后处死所有大鼠,取结肠标本评价结肠湿重指数,生化法检测血清中髓过氧化物酶（MPO）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和一氧化氮合酶（iNOS）活力及丙二醛（MDA）、谷胱甘肽（GSH）和NO含量。结果：与模型对照组比较,GSPE各剂量组大鼠体重下降程度较轻（P〈0.05或P〈0.01）,结肠湿重指数明显降低（P〈0.05或P〈0.01） 大鼠血清中MPO和iNOS活力及MDA和NO含量均明显降低（P〈0.05或P〈0.01） 大鼠血清中SOD和GSH-Px活力及GSH含量明显升高（P〈0.05或P〈0.01）。结论：GSPE可能通过提高复发性结肠炎大鼠血清抗氧化能力,抑制NO生成,来减轻复发性结肠炎炎症反应。     

银杏叶提取物对大鼠实验性结肠炎肿瘤坏死因子-α表达的影响

目的观察银杏叶提取物对三硝基苯磺酸灌肠诱导大鼠实验性结肠炎肿瘤坏死因子-α(TNF-α)的影响及其作用机制。方法大鼠随机分为正常对照组、三硝基苯磺酸模型组、阳性药物对照组、EGB组4组。用三硝基苯磺酸灌肠诱导大鼠实验性结肠炎,评估结肠组织大体形态和组织学评分;生化法检测大鼠肠组织谷胱苷肽过氧化物酶(GSH-Px)活性及一氧化氮(NO)含量;免疫组化检测肠组织TNF-α,核因子-κBp65(NF-κBp65)蛋白表达。逆转录聚合酶链反应(RT-PCR)检测肠组织诱生型一氧化氮合酶(iNOS)表达。结果EGB组大体形态和组织学评分较模型组明显下降,GSH-Px活性明显增高,NO含量明显减少,结肠黏膜TNF-α,NF-KBp65和iNOS表达明显降低。结论EGB可能通过抑制TNF-α的表达和NF-κBp65及iNOS的激活从而抑制炎症级联来保护TNBS诱导的实验性结肠炎。