肝窦毛细血管化的形成机制研究

目的　探讨二甲基亚硝胺 (DMN)致大鼠肝纤维化过程中肝窦壁病理变化及其与门脉压力的关系。方法　雄性Wistar大鼠 4 0只用 0 .5 %DMN每周连续 3d共 4周 12次腹腔注射制作大鼠肝纤维化模型 ,分别于造模后 1d、2d、3d、1周、2周、4周、6周、8周作为动态观察时相点 ;分别取 5只模型大鼠和 3只正常大鼠肠系膜前静脉分支插管法测门脉压力 (Ppv) ;免疫组化染色观察肝组织Ⅳ型胶原(ColⅣ )、层粘连蛋白 (LM)和Ⅰ型胶原 (ColⅠ )表达 ;透射电镜观察肝组织超微结构。结果　正常大鼠肝窦壁ColⅣ阳性表达 ;模型组肝窦壁除ColⅣ阳性染色呈现为先弱后强外 ,LM和ColⅠ的沉积均随造模时间的延长而进行性增加 ,4周时表达最为明显 ,电镜下可见肝窦内皮失窗孔和内皮下完整基底膜形成 ;模型组Ppv与肝窦壁LM的表达量呈显著正相关 (P <0 .0 5 )。结论　DMN大鼠肝窦内皮下基底膜是在功能性基底膜破坏的基础上 ,随着LM与新合成ColⅣ沉积以及两者结合的增加、加之ColⅠ的沉积而形成     

肝窦毛细血管化在二甲基亚硝胺大鼠肝纤维化门静脉高压形成中的作用

目的 研究肝窦毛细血管化在二甲基亚硝胺(DMN)大鼠肝纤维化门静脉高压形成中的作用。方法经4周12次腹腔注射DMN制备火鼠肝纤维化模型,应用电镜技术、免疫组织化学方法结合大鼠门静脉压力测定,24周动态分析肝纤维化形成过程中肝窦毛细血管化与门静脉压力变化的相关性。结果 大鼠门静脉压力随着造模的进行不断升高,造模4周时达(1.10 ±0.18)kPa,明显高于对照组(0.52±0.04)kPa(t=6.41.P<0.0 1)。造模停止后,大鼠门静脉压力逐渐恢复正常。其动态变化与电镜下肝窦毛细血管化的变化规律一致;与反映肝窦内皮表型改变的第Ⅷ因子相关抗原的动态变化成正相关(r=0.833,P<0.01);与反映肝窦内皮下基底膜形成的层黏连蛋白的动态变化成正相关(r=0.953,P<0.01);与反映肝窦壁星状细胞活化收缩的α-平滑肌肌动蛋白的动态变化成正相关(r=0.919,P<0.01)。结论 肝窦毛细血管化是DMN肝纤维化模型门静脉高压产生的主要原因。     

FibroScan评估酒精性肝病肝纤维化程度的诊断价值

目的探讨瞬时弹性成像技术(FibroScan)在评估酒精性肝病肝纤维化程度中的应用价值。方法对60例酒精性肝病患者采用FibroScan测量肝脏硬度,获得FibroScan弹性值(FS值),同时对患者进行肝活组织检查.以病理结果为金标准,分析FS值与酒精性肝纤维化分期的相关性。用受试者工作特征(receiver operatmg charateristic,R()C)曲线评估FibroScan对酒精性肝病的诊断价值。结果酒精性肝病患者肝纤维化分期S0~S4的FS值分别为S0:(5.31±1.06)kPa、S1:(7.91±2.81)kPa、S2:(9.81±3.39)kPa、S3:(14.66±4.31)kPa、S4:(19.81±6.02)kPa。组间差异有统计学意义(P0.(5)。进一步分析显示FS值与肝纤维化分期呈正相关性(r=0.706,P0.05)。肝纤维化程度≥S1、≥S2、≥S3和S4的ROC曲线下面积分别为0.833、0.871、0.906和0.919。结论 Fibroscan作为一种无创技术,能够较准确地定量评估酒精性肝病肝纤维化程度。     

内源性硫化氢与肝脏纤维化

硫化氢被证实是存在于体内的第三种新型的内源性气体信号分子,有着广泛的生物学效应。近年研究证实其在肝纤维化的发生发展过程中起着重要的保护性作用。对其进一步的研究,将为肝纤维化及门脉高压的临床治疗提供新的方向。     

Establishment of a hepatic cirrhosis and portal hypertension model by hepatic arterial perfusion with 80% alcohol

AIM: To determine the feasibility and safety of establishing a porcine hepatic cirrhosis and portal hypertension model by hepatic arterial perfusion with 80% alcohol.METHODS: Twenty-one healthy Guizhou miniature pigs were randomly divided into three experimental groups and three control groups. The pigs in the three experimental groups were subjected to hepatic arterial perfusion with 7, 12 and 17 mL of 80% alcohol, respectively, while those in the three control groups underwent hepatic arterial perfusion with 7, 12 and 17 mL of saline, respectively. Hepatic arteriography and direct portal phlebography were performed on all animals before and after perfusion, and the portal venous pressure and diameter were measured before perfusion, immediately after perfusion, and at 2, 4 and 6 wk after perfusion. The following procedures were performed at different time points: routine blood sampling, blood biochemistry, blood coagulation and blood ammonia tests before surgery, and at 2, 4 and 6 wk after surgery; hepatic biopsy before surgery, within 6 h after surgery, and at 1, 2, 3, 4 and 5 wk after surgery; abdominal enhanced computed tomography examination before surgery and at 6 wk after surgery; autopsy and multi-point sampling of various liver lobes for histological examination at 6 wk after surgery.RESULTS: In experimental group 1, different degrees of hepatic fibrosis were observed, and one pig developed hepatic cirrhosis. In experimental group 2, there were cases of hepatic cirrhosis, different degrees of increased portal venous pressure, and intrahepatic portal venous bypass, but neither extrahepatic portal-systemic bypass circulation nor death occurred. In experimental group 3, two animals died and three animals developed hepatic cirrhosis, and different degrees of increased portal venous pressure and intrahepatic portal venous bypass were also observed, but there was no extrahepatic portal-systemic bypass circulation.CONCLUSION: It is feasible to establish an animal model of hepatic cirrhosis and portal hypertension by hepatic arterial perfusion with 80% alcohol, however, the safety of this model depends on a suitable perfusion dose.     

肝纤维化小鼠肝组织血管新生特点及其形成机制

目的 探讨肝纤维化小鼠肝组织血管新生特点及其形成机制.方法 C57BL/6小鼠随机分为正常对照组与模型18 h、4周、8周组,共4组.采用CCl4诱导小鼠肝纤维化模型.天狼猩红染色观察肝组织胶原沉积;免疫荧光检测肝组织vWF蛋白表达,分析微血管密度;扫描电镜及透射电镜观察肝窦内皮结构;Western blot法检测肝组...     

Effects of simvastatin, pentoxifylline and spironolactone on hepatic fibrosis and portal hypertension in rats with bile duct ligation

Aims/Methods: Our aim was to the antifibrotic and hemodynamic effects of simvastatin (SMV), pentoxifylline (PTX) and spironolactone (SPN), three drugs which may have antifibrotic and/or portal hypotensive properties, in a model of hepatic fibrosis and portal hypertension induced in rats by bile duct ligation. A blind study was performed in five groups of 53 Sprague-Dawley rats: sham, placebo (PL), SMV (2.5 mg·kg⁻¹·J⁻¹, PTX (50 mg·kg⁻¹·J⁻¹) and SPN (100 mg·kg⁻¹·J⁻¹). Drugs were administered by daily gavage over a 4-week period as soon as bile duct ligation was performed. At day 28, the following parameters were evaluated: area of hepatic fibrosis by image analysis after staining collagen with picrosirius and plasma concentrations of hyaluronate, splanchnic and systemic hemodynamics (radiolabeled microspheres).Results: Portal venous pressure (PL: 15.5±1.5, SMV: 15.8±2.5, PTX: 15.9±1.8, SPN: 13.5±2.1 mmHg, p<0.05) and porto-systemic shunts (PL: 30±31, SMV: 18±27, PTX: 25±24, SPN: 5±4%, p<0.05) were significantly reduced in the SPN group; other hemodynamic parameters were not significantly altered. There was a significant correlation between porto-systemic shunts and portal pressure (r_s=0.47, p<0.01). The area of fibrosis was not significantly different among the four groups of bile duct ligated rats (PL: 8.7±3.9, SMV: 7.1±3.6, PTX: 7.8±2.7, SPN: 6.6±3.3%) but was higher than in sham rats (1.5±0.5%, p<0.001). Hyaluronate was significantly higher in bile duct ligated rats (from 374±162 to 420±131 μg/l, among the four groups) than in sham rats (52±16 μg/l, p<0.0001).Conclusions: In this model, none of the drugs prevented hepatic fibrosis. On the other hand, spironolactone decreased portal pressure and prevented porto-systemic shunts. Therefore, this drug may have beneficial effect in patients with early portal hypertension.     

A pharmacodynamic model of portal hypertension in isolated perfused rat liver

AIM: To develop a pharmacodynamic model of portal hypertension from chronic hepatitis.METHODS: Pathological changes and collagen depositions were analyzed using morphometry to confirm CCl₄-induced chronic hepatitis. At d₀, d₂₈, d₅₆ and d₈₄ of the process, the portal perfused velocities (μL/min) in isolated rat livers were exactly controlled with a quantified pump. The pressure (mmHg) was monitored with a Physiological System. The geometric concentrations of phenylephrine or acetylcholine were added to a fixed volume (300 mL) of the circulating perfusate. The equation, the median effective concentration and its 95% confidence intervals of phenylephrine or acetylcholine were regressed with Prism-4 software in non-linear fit and various slopes. In the isolated perfused rat livers with chronic hepatitis, both median effective concentrations were defined as the pharmacodynamic model of portal hypertension.RESULTS: At d₀, d₂₈, d₅₆ and d₈₄, the equations of portal pressure potency from the concentrations of phenylephrine used to constrict the portal vein in isolated perfused rat livers were Y = 0.1732 + 0.3970/[1 + 10^{(-4.3061-0.4407 X)}], Y = -0.004934 + 0.12113/[1 + 10^{(-3.1247-0.3262 X)}], Y = 0.0104 + 0.2643/[1 + 10^{(-8.8462-0.9579 X)}], and Y = 0.01603 + 0.12107/[1 + 10^{(-5.1134-0.563 X)}]; the median effective concentrations were 1.69 × 10^-10 mol/L, 2.64 × 10^-10 mol/L, 5.82 × 10^-10 mol/L, and 8.24 × 10^-10 mol/L, respectively. The equations from the concentrations of acetylcholine used to relax the portal vein were Y = -0.4548 + 0.3274/[1 + 10^{(6.1538 + 0.5554 X)}], Y = -0.05391 + 0.06424/[1 + 10^{(3.8541 + 0.3469 X)}], Y = -0.2733 + 0.22978/[1 + 10^{(3.0472 + 0.3008 X)}], and Y = -0.0559 + 0.053178/[1 + 10^{(5.6336 + 0.5883 X)}]; the median effective concentrations were 8.40 × 10^-10 mol/L, 7.73 × 10^-12 mol/L, 5.98 × 10^-11 mol/L, and 2.66 × 10^-10 mol/L, respectively.CONCLUSION: A pharmacodynamic model of portal hypertension in isolated perfused rat livers with chronic hepatitis was defined as the median effective concentrations of phenylephrine and acetylcholine.     

Noncirrhotic portal fibrosis/idiopathic portal hypertension: APASL recommendations for diagnosis and treatment

The Asian Pacific Association for the Study of the Liver (APASL) Working Party on Portal Hypertension has developed consensus guidelines on the disease profile, diagnosis, and management of noncirrhotic portal fibrosis and idiopathic portal hypertension. The consensus statements, prepared and deliberated at length by the experts in this field, were presented at the annual meeting of the APASL at Kyoto in March 2007. This article includes the statements approved by the APASL along with brief backgrounds of various aspects of the disease.     

门静脉高压状态下门体分流的超声分型及分流量与肝性脑病的关系

门静脉高压门体分流性肝性脑病,常为肝硬化患者致死原因之一,本研究旨在探讨门静脉高压状态下门体分流的超声分型及分流量与肝性脑病的关系,为临床提供诊断、治疗依据。一、资料与方法1.对象:2000年5月至2005年5月我院住院肝硬化患者分为门体分流组和无分流组。分流组:667例存在自发性     

肝硬化门静脉高压异位静脉曲张破裂出血的识别与治疗

由于肝硬化门静脉高压异位静脉曲张破裂出血诊断困难、出血量大、止血困难、预后差、死亡率高,其早期识别和治疗是困扰临床工作的一个难题.本文对肝硬化门静脉高压异位静脉曲张破裂出血的识别与治疗进行综述.     

四氯化碳诱导的肝纤维化大鼠肝窦毛细血管化的形成

目的：观察四氯化碳（CCl4）诱导的大鼠肝纤维化过程中肝窦毛细血管化的形成过程,探讨其与肝纤维化的关系。方法32只清洁级雄性SD大鼠,随机分为正常对照组,肝纤维化模型组,正常对照组大鼠腹腔注射0．9％氯化钠溶液2 mL/kg ,模型组大鼠腹腔注射50％ CCl4-蓖麻油混合液2 mL/kg ,每周2次,共8周;分别于造模第2、4、6、8周处死大鼠,观察肝组织炎症及纤维化程度,放射免疫法检测血清中透明质酸（HA）的含量,透射电镜观察肝窦窦壁结构,S-P 免疫组织化学检测各组大鼠肝组织CD31、层黏连蛋白（LN）、IV型胶原（Col-IV）的表达。结果肝脏组织学证实CCl4诱导的大鼠肝纤维化模型构建成功,6周可见纤维间隔形成;透射电镜显示,CCl4诱导2周时,部分肝窦内皮细胞（liver sinusoidal endothelial cells ,LSEC）窗孔减少,内皮下未见基底膜（Basement membrane,BM）,随着造模的进程,LSEC 窗孔进一步减少,部分甚至消失,第6、8周时局部肝窦内皮下形成连续的BM。同时,随着肝纤维化的进程,HA浓度逐渐升高,肝窦内皮细胞表面标志物CD31及基底膜主要成分Col-IV、LN表达逐渐增强。结论在CCl4诱导大鼠肝纤维化过程中,肝窦毛细血管化是逐渐形成的,LSEC失窗孔早于纤维间隔的形成,而肝窦内皮下基底膜出现在纤维间隔形成以后。     

Agreement between wedged hepatic venous pressure and portal pressure in non-alcoholic steatohepatitis-related cirrhosis

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Stability of a rat model of prehepatic portal hypertension caused by partial ligation of the portal vein

AIM： To study the stability of portal hypertension （PHT） caused by partial ligation of the portal vein ligation （PVL） in a rat model.
METHODS： Thirty male adult Wistar rats were divided into two groups： 10 in Group Ⅰ received a sham operation; and 20 in Group Ⅱreceived partial PVL. Portal vein pressure （PVP） was measured at four time periods： before ligation, 2 wk, 6 wk and 10 wk postsurgery. Portal venography, blood sampling and liver and spleen pathological examinations were conducted at 10 wk after surgery.
RESULTS： The PVP was 9.15± 0.58 cmH2O before ligation, and increased to 17.32 ±0.63 cmH2O 2 wk after PVL. By repeat measurement of the PVP in each rat, it was shown to remain elevated for 10 wk. There were no significant differences in the pressure measurements at 2 wk, 6 wk and 10 wk. Varices were found mainly in the mesenteric vein 2 wk after PVL, which were more obvious later, while these manifestations were similar at week 6 and week 10. Portal venography demonstrated the varices and collaterals. There was no significant change in liver pathology. The volume of the spleen was enlarged 2-fold after ligation, and the sinus of the spleen was enlarged due to congestion. Significant sinus endothelial cell proliferation was observed, but no evidence of hypersplenia was found on hemogram and biochemical examination.
CONCLUSION： These findings suggest that a satisfactory prehepatic PHT rat model can be obtained by partial ligation of the portal vein, and this PHT rat model was stable for at least 10 wk.     

Splanchnic-aortic inflammatory axis in experimental portal hypertension

Splanchnic and systemic low-grade inflammation has been proposed to be a consequence of long-term prehepatic portal hypertension.This experimental model causes minimal alternations in the liver,thus making a more selective study possible for the pathological changes characteristic of prehepatic portal hypertension.Low-grade splanchnic inflammation after longterm triple partial portal vein ligation could be associated with liver steatosis and portal hypertensive intestinal vasculopathy.In fact,we have previously shown that prehepatic portal hypertension in the rat induces liver steatosis and changes in lipid and carbohydrate metabolism similar to those produced in chronic inflammatory conditions described in metabolic syndrome in humans.Dysbiosis and bacterial translocation in this experimental model suggest the existence of a portal hypertensive intestinal microbiome implicated in both the splanchnic and systemic alterations related to prehepatic portal hypertension.Among the systemic impairments,aortopathy characterized by oxidative stress,increased levels of proinflammatory cytokines and profibrogenic mediators stand out.In this experimental model of long-term triple portal vein ligated-rats,the abdominal aortic proinflammatory response could be attributed to oxidative stress.Thus,the increased aortic reduced-nicotinamide-adenine dinucleotide phosphate[NAD(P)H]oxidase activity could be associated with reactive oxygen species production and promote aortic inflammation.Also,oxidative stress mediated by NAD(P)H oxidase has been associated with risk factors for inflammation and atherosclerosis.The splanchnic and systemic pathology that is produced in the long term after triple partial portal vein ligation in the rat reinforces the validity of this experimental model to study the chronic low-grade inflammatory response induced by prehepatic portal hypertension.     

Pan-PPAR agonist lanifibranor improves portal hypertension and hepatic fibrosis in experimental advanced chronic liver disease

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Extrahepatic aneurysm of the portal venous system and portal hypertension

Portal venous aneurysm (PVA) is a rare condition characterized by dilatation of the portal venous system. PVA manifestation of symptoms is varied and depends on the aneurysm size, location and related-complications, such as thrombosis. While the majority of reported cases of PVA are attributed to portal hypertension, very little is known about the condition’s pathophysiology and clinical management remains a challenge. Here, we describe a 67-year-old woman who presented with complaint of dyspepsia and without a significant medical history, for whom PVA was incidentally diagnosed. The initial upper abdominal ultrasound revealed marked dilatation of the main portal vein, and subsequent contrast-enhanced computed tomography with angiography revealed a large aneurysm arising from the extrahepatic troncus portion of the portal vein, as well as gastroesophageal varices. A conservative approach using beta-blocker therapy was chosen. The patient was followed-up for 60 mo, during which time the asymptomatic status was unaltered and the PVA remained stable.