二丁基二氯化物尾静脉注射建立大鼠慢性胰腺炎模型

目的 探讨经尾静脉注射二丁基二氯化物建立大鼠慢性胰腺炎模型的方法,为慢性胰腺炎纤维化机制研究提供一种合适的动物模型.方法 将SD大鼠随机分为实验组和对照组,每组再分为1,7,14,21,28,60 d 6个观察点,每个时间点各5只大鼠.实验组大鼠尾静脉注射二丁基二氯化物8 mg/kg体重,对照组注射相同剂量的乙醇和甘油溶剂.上述时间点分别处死大鼠,收集血液和胰腺标本.检测血清淀粉酶、脂肪酶、透明质酸浓度.观察胰腺形态,病理改变,胶原染色评价纤维化程度.结果 造模后1 d胰腺组织水肿,表现为急性中度间质性水肿性胰腺炎;7 d炎症加重,表现为腺泡肿胀,散在的腺泡细胞坏死;14 d广泛的炎症细胞浸润,伴轻度纤维化;21 ～ 28 d胶原沉积,纤维化加重,可见大量的纤维结缔组织;60 d,胰腺小叶结构破坏,腺泡消失,广泛间质纤维化.结论 尾静脉注射二丁基二氯化物是一种简便、有效的大鼠慢性胰腺炎模型制作方法,能为慢性胰腺炎纤维化的研究提供合适的动物模型.     

大鼠慢性酒精中毒模型的建立及病理学观察

直接饮用含酒精水建立不同程度大鼠慢性酒精中毒模型,以饮用不含酒精水大鼠作对照组,提取模型组和对照组大鼠的大脑和肝脏进行病理学观察.发现模型组死亡率13.3%,对照组无一死亡;模型组大鼠性情不稳定、呆板、嗜睡、行走不稳,体质量较对照组明显减轻(P<0.01);模型组大鼠有脑血管及细胞组织的病理改变,肝脏有脂肪变性和肝炎的病理改变.认为直接饮用含酒精水的动物造模方法简单易行,适合于慢性酒精中毒动物模型的制备,但造模成功率低,造模标本不标化.     

L-精氨酸诱导实验性慢性胰腺炎大鼠模型的可行性分析

目的 初步探讨L-精氨酸诱导慢性胰腺炎大鼠动物模型的可行性.方法 将实验动物按完全随机法分为对照组及精氨酸12、24 h和7 d组,每组10只,间隔1 h分两次腹腔内注射L-精氨酸溶液造模.造模后相应时间点检测血淀粉酶、血糖水平,对胰腺组织进行病理评分,Van Gieson法对胰腺胶原纤维染色.结果 对照组及精氨酸12、24 h和7 d组的血淀粉酶水平分别为(1 634±890)U/L、(3 872±2 676)U/L、(3 307±2 197)U/L和(1 561±304)U/L,精氨酸7 d组血淀粉酶水平显著低于12 h和24 h组(P＜0.05),恢复到对照组水平.各组间血糖水平无明显差异.对照组及精氨酸12、24 h和7 d组胰腺的病理分值分别为0.8±0.4、5.1±2.6、6.5±2.2和4.5±1.6,精氨酸7 d组胰腺病理评分显著低于24 h组(P＜0.05),但仍显著高于对照组(P＜0.05).精氨酸7 d组胶原染色范围明显增加,其他各组未见明显胶原染色.结论 L-精氨酸腹腔注射后7 d可引起胰腺组织纤维化及管状复合结构增生,可用于探索慢性胰腺炎大鼠模型.     

慢性胰腺炎实验模型研究进展

近几年 ,我国慢性胰腺炎的发病率呈上升趋势 ,然而有关其确切的发病机制 ,以及基于此而建立的临床诊断和治疗措施尚远不够成熟。其主要原因之一在于缺乏适合研究慢性胰腺炎的实验模型。为此 ,一些学者在该领域进行了一些探索性研究。现将相关的研究作一概述。一、动物模型的制备慢性胰腺炎动物模型的建立经历了若干阶段 ,但可重复的慢性胰腺炎动物模型仍面临挑战。最初的设想是制备慢性酒精性胰腺炎的动物模型。早在 1968年 ,有学者[1] 提出灌注大鼠或狗乙醇时可观察到胰腺实质纤维化和胰管蛋白栓子的形成 ,但未能被其他研究所证实 ,唯一达…     

慢性胰腺炎

据估测,慢性胰腺炎的流行率约为0.04％～5％。在发达国家,60％～70％的慢性胰腺炎患者在临床症状出现前有长期(6～12年)嗜酒(每天150～170克)史。高蛋白饮食可加重酒精的损伤作用。酒精引起的胰腺炎高发于35～45岁的男性。创伤后胰管狭窄、假性囊     

慢性胰腺炎与胰腺癌

慢性胰腺炎与胰腺癌虽分属良、恶性两种疾病,但可有相似的临床表现及影像学检查结果,有时鉴别诊断非常困难。这两种疾病有时可能互为因果,增加对它们各自特征及相互关系的认识,有助于恰当地诊治这两种疾病。 一、慢性胰腺炎与胰腺癌的病理 胰腺癌病灶与周围正常胰腺组织分界不很清楚,常深埋于胰腺实质中,切面呈黄白或灰白色;慢性胰腺炎可有广泛的纤雏化及不规则结节样硬化。在一组接受手术的慢性胰腺炎患者中,约３０％有胰腺炎性肿块,与胰腺癌在肉眼上难以鉴别,故术中常需冰冻切片,通过组织学检查确定病理诊断。慢性胰腺炎与胰腺…     

大鼠急性胰腺炎病理学特征与氧自由基变化的关系

急性胰腺炎(AP)是临床常见的急腹症之一,其病因及发病机制至今尚未完全明确,近年来研究提示细胞因子及炎症递质在AP病程演变过程中起着一定的作用,而氧自由基在AP发病中的作用尤为重要,甚至认为起着始动作用[1].我们应用"十二指肠闭袢法"制备AP大鼠模型,在光、电镜水平研究其病理变化的特征,并检测各时期血浆过氧化脂质的含量,探讨与AP大鼠病理学特征之间的关系.     

大鼠急性胰腺炎模型建立的探究

目的 建立一种简单易行和稳定可靠的L-精氨酸诱导的急性胰腺炎模型,以便对治疗急性胰腺炎的疗效进行观察和探讨.方法 选择36只健康SD大鼠,采用15％和20％不同浓度的L-精氨酸溶液（用0.9％的生理盐水配制而成）1.5 g/kg腹腔内注射入大鼠体内,分别于不同的时间点取材,分别检测大鼠的存活率、血生化指标中的血清淀粉酶和脂肪酶以及大鼠胰腺的病理变化.结果 15％L-精氨酸溶液腹腔注射大鼠的生存率明显高于20％组,实验组的动物12h后血清淀粉酶和血清脂肪酶水平明显升高,显著高于对照组（P ＜0.0001）,但两实验组之间差异无统计学意义（P＞0.05）,病理结果显示胰腺腺泡结构紊乱,大量腺泡细胞水肿、坏死,出现核固缩,胞内空泡形成,小叶间隙增宽并伴有炎性细胞浸润及出血.20％L-精氨酸组病理改变较严重,腺泡和导管消失并伴有皂化斑形成.结论 应用15％ ～ 20％的L-精氨酸溶液1.5 g/kg的剂量可致不同程度的比较稳定的急性胰腺炎模型.并且其浓度大小决定胰腺损伤的程度.15％L-精氨酸所致急性胰腺炎是比较理想的模型.     

慢性胰腺炎动物模型的建立

本研究首次报道通过胰管内注入三硝基苯磺酸（trini-trobenenze sulfonic acid,TNBS）,成功诱导大鼠慢性胰腺炎模型。     

Pathophysiology of chronic pancreatitis induced by dibutyltin dichloride joint ethanol in mice

AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis.METHODS: The mice were randomly divided into 2 groups(n = 50), control group and model group. The mice in model group were given ethanol(10%) in drinking water after injection of dibutyltin dichloride(DBTC)(8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein( 60 % ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin(FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen typeⅠ(COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1(MMP-1) and tissue inhibitor of metalloproteinases-1(TIMP-1) m RNA in the pancreas was assessed by real time PCR.RESULTS: DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group(P 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 m RNA in pancreas decreased, but TIMP-1 m RNA increased at model group.CONCLUSION: DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis.     

Cytokine mRNA levels and lymphocyte infiltration in pancreatic tissue during experimental chronic pancreatitis induced by dibutyltin dichloride

There is little information available regarding the role of inflammatory cells in the pathogenesis of chronic pancreatitis. Therefore, we analyzed the local cytokine profile and infiltrating lymphocytes in a rat model of chronic pancreatitis. Experimental pancreatitis was induced by a single intravenous application of dibultyltin dichloride (DBTC). During a time course of two months we observed the mRNA expression of cytokines using competitive RT-PCR. Lymphocytes were characterized by immunohistochemistry, FACS analysis, and the lymphocyte proliferation test. IL-1, IL-6, IL-5, and IL-10 were immediately up-regulated in the acute phase of disease, while lymphocyte-restricted expression of IL-2, IL-2R, and IFN- was only found in the chronic course. Among the infiltrating lymphocytes, CD4⁺ cells dominated, but during the chronic process there was an increase of CD8⁺ cells, resulting in a reduced CD4/CD8 ratio. Mitogen-induced activation of isolated mesenteric lymph node cells increased during the chronic inflammation. Our results suggest that in experimental pancreatitis acute inflammatory reactions are followed by a T-lymphocyte-mediated process.     

巴马小型猪轻度慢性胰腺炎代谢特征分析

目的 应用高分辨魔角旋转磁共振（HR-MAS NMR）波谱分析巴马小型猪阻塞性慢性胰腺炎（CP）早期的代谢变化特征.方法 39头巴马小型猪按随机数字表法分为对照组和CP组.采用主胰管近端不全结扎法制备CP模型,对照组仅开腹翻动胰腺及肠道后关腹.造模后第4、8、12周分批处死动物,获取胰腺组织.根据胰腺纤维化程度,将CP分为轻、中、重度.应用HR-MAS NMR波谱分析轻度CP组和对照组胰腺组织的代谢特征.结果 制模成功的24头巴马小型猪的胰腺组织经病理检查为轻度10头,中度5头,重度7头.经HR-MAS NMR波谱分析,轻度CP组胰腺组织的代谢产物中胆碱、甘氨酸、甜菜碱、乳酸、脂肪酸、磷酸胆碱/甘油磷酸胆碱峰值与对照组有差异,其中胆碱波峰显著增高,差异有统计学意义（5.02 ±1.96比1.56 ±0.79,P＜0.01）,而其他5种代谢产物峰的差异均无统计学意义.结论 与对照组比较,巴马小型猪轻度CP胰腺组织的胆碱波峰强度显著增高,这可能是区分正常和早期CP的标志.     

Increased heat shock protein 70 expression attenuates pancreatic fibrosis induced by dibutyltin dichloride

Abstract

Objectives: Heat shock protein (HSP) 70 performs a chaperoning function and protects cells against injury. Although the effect of HSPs against acute inflammatory change has been proven, the relationship between HSP70 and chronic pancreatitis remains unclear. This study aimed to investigate the protective effect of increased HSP70 expression induced by thermal stress against pancreatic fibrosis in experimental chronic pancreatitis.

Materials and Methods: Two experiments to evaluate pancreatic HSP70 expression induced by thermal stress and determine the effect of increased HSP70 expression against pancreatic fibrosis were performed. To investigate HSP70 expression, rats were immersed in a warm bath and sequentially killed, and pancreatic HSP70 expression was measured. To study the effect of increased HSP70 expression, pancreatic fibrosis was induced by intravenous injection of dibutyltin dichloride (DBTC) and analyzed under repeated thermal stress. The severity of pancreatic fibrosis was measured.

Results: Thermal stress significantly increased HSP70 expression in the pancreas. HSP70 expression peaked at 6–12?h after warm bathing, and the increased HSP70 expression was associated with the attenuation of pancreatic fibrosis. Although pancreatic fibrosis was induced by DBTC injection, HSP70 expression induced by repeated thermal stress diminished the severity of atrophy and fibrosis. On western blot analysis, collagen type 1 expression was diminished in the increased HSP70 expression group, but not α-smooth muscle actin expression.

Conclusions: Thermal stress could increase pancreatic HSP70 expression, and induced HSP70 expression showed a protective effect against pancreatic fibrosis. Modulation of HSP70 expression could be a potential therapeutic target in the treatment of chronic pancreatitis.     

Protective effects of edaravone on experimental chronic pancreatitis induced by dibutyltin dichloride in rats

Background/aimsTo investigate the effects of edaravone, a potent free radical scavenger, on dibutyltin dichloride (DBTC)-induced chronic pancreatitis (CP) and pancreatic fibrosis.MethodsMale Sprague–Dawley rats were randomly divided into four groups (n = 16 each): control, DBTC, DBTC + edaravone, and control + edaravone. Edaravone or normal saline at a daily dose of 6 mg/kg body weight was given intraperitoneally from day 5 to day 28 after DBTC administration. On days 14 and 28, the rats were evaluated morphologically and biochemically. The expression of cytokines in pancreas TGF-β, IL-6 and TNF<alpha> was detected using RT-PCR. The activation of nuclear factor (NF)-κB in pancreatic tissue was evaluated by immunostaining and western-blot for NF-κB p65. α-smooth muscle actin (α-SMA) expression was also evaluated by immunostaining and western-blot to investigate the activation of pancreatic stellate cells (PSCs).ResultEdaravone treatment improved the rats' body weight (p < 0.01) and feed intake levels (p < 0.05), improved the histological scores and alleviated the fibrosis of pancreas samples (p < 0.05), as well as markedly increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) concentrations in pancreatic tissue (p < 0.01 for both). The expression of cytokines TGF-β, IL-6 and TNF<alpha> in pancreas of DBTC group was also down-regulated by edaravone after treatment. Edaravone inhibited the activation of NF-κB and PSCs and exhibited protective effects on pancreatic tissue damage in CP.ConclusionsThis antioxidant may be a promising therapeutic intervention for human CP.     

Anti-monocyte chemoattractant protein 1 gene therapy attenuates experimental chronic pancreatitis induced by dibutyltin dichloride in rats

BACKGROUND: Monocyte chemoattractant protein 1 (MCP-1) is a member of the C-C chemokine family and exerts strong chemoattractant activity in monocytes, macrophages, and lymphocytes. Rat pancreatic fibrosis induced by dibutyltin dichloride (DBTC) is considered to be an appropriate chronic pancreatitis model histologically and enzymatically, as has demonstrated in a previous study. AIM: We examined the effect of human dominant negative inhibitor of MCP-1 (mutant MCP-1) on progression of chronic pancreatitis induced by DBTC in a rat model. METHODS: We used the experimental model of chronic pancreatitis induced by DBTC in rats. Mutant MCP-1 or empty plasmid at a dose of 50 microg/body weight was administrated into rat thigh muscles on days 4, 11, and 18 after administration of DBTC. On days 14 and 28, we evaluated the effect of mutant MCP-1 morphologically and biochemically. RESULTS: The mutant MCP-1 treated group inhibited early pancreatic inflammation and later pancreatic fibrosis histologically, and showed a decrease in serum MCP-1 concentration, intrapancreatic hydroxyproline, alpha-smooth muscle actin, and an increase in intrapancreatic amylase and protein content compared with the empty plasmid treated group. The mutant MCP-1 group also inhibited intrapancreatic mRNA expression of cytokines and chemokines. CONCLUSIONS: : Our findings suggest that monocyte/macrophage recruitment and the systemic MCP-1 signal pathway contribute to progression of chronic pancreatitis, and that blockade of MCP-1 may suppress the development of pancreatic fibrosis.