Hemodynamic evaluation of the right portal vein in healthy dogs of different body weights

Background  

Doppler ultrasonography is an important tool for evaluating hepatic portal hemodynamics. However, no study in dogs of different body weights, in the range encountered in routine clinical veterinary practice, has been reported. It can be difficult to obtain an ideal insonation angle when evaluating the main portal vein, so evaluation of the right portal vein branch has been described in humans as an alternative. The aim of this study was to analyze, through Doppler ultrasonography, the hemodynamics in the right portal vein branch in dogs of different body weights.     

Inherited liver shunts in dogs elucidate pathways regulating embryonic development and clinical disorders of the portal vein

Congenital disorders of the hepatic portal vasculature are rare in man but occur frequently in certain dog breeds. In dogs, there are two main subtypes: intrahepatic portosystemic shunts, which are considered to stem from defective closure of the embryonic ductus venosus, and extrahepatic shunts, which connect the splanchnic vascular system with the vena cava or vena azygos. Both subtypes result in nearly complete bypass of the liver by the portal blood flow. In both subtypes the development of the smaller branches of the portal vein tree in the liver is impaired and terminal branches delivering portal blood to the liver lobules are often lacking. The clinical signs are due to poor liver growth, development, and function. Patency of the ductus venosus seems to be a digenic trait in Irish wolfhounds, whereas Cairn terriers with extrahepatic portosystemic shunts display a more complex inheritance. The genes involved in these disorders cannot be identified with the sporadic human cases, but in dogs, the genome-wide study of the extrahepatic form is at an advanced stage. The canine disease may lead to the identification of novel genes and pathways cooperating in growth and development of the hepatic portal vein tree. The same pathways likely regulate the development of the vascular system of regenerating livers during liver diseases such as hepatitis and cirrhosis. Therefore, the identification of these molecular pathways may provide a basis for future proregenerative intervention.     

Method for continuous infusion into the portal vein of mice

Recombinant retroviral vectors are attractive for in vivo gene transfer into the liver because they integrate into the host-cell genome, resulting in permanent gene expression. Gene-transfer efficiency can be improved by increasing the number of retroviral particles delivered to hepatocytes. For this purpose, we report a mouse model for continuous infusion into the portal circulation permitting large-volume vector administration, which will allow marked increase in gene-transfer efficiency. Continuous saline infusion was evaluated, using various parameters, and an infusion rate of 6 ml/24 h was found safe and well tolerated for at least 2 weeks. No significant changes in liver and kidney function and electrolyte balance were observed during the infusion. In addition to providing a valuable method for in vivo hepatic gene therapy, this model has a number of other potential applications, including mouse studies of hepatic tumor therapy, pharmacology, toxicology, and liver biology.     

门静脉海绵样变大鼠门静脉氧化应激损伤的研究

目的:考察门静脉海绵样变性(CTPV,Cavernous transformation of portal vein)大鼠体内氧化应激的状态以及氧化应激对门静脉结构的影响。方法:采用门脉部分结扎法复制CTPV大鼠动物模型;通过测定门静脉内血浆超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活力来分析机体抗氧化能力,测定丙二醛(MDA)含量分析机体氧化能力;门静脉HE染色观察门静脉病理变化。结果:Sham组大鼠门静脉造影显示门静脉通畅,无曲张与扩张;门静脉病理学检查显示门静脉管腔无增大、内皮细胞光滑、中膜平滑肌层无增厚、外膜完整。CTPV组大鼠门静脉造影显示门静脉周围侧支循环形成,门静脉病理检查显示多个管腔大小不一、外形不规则血管腔,管腔之间为较狭窄的纤维性间隔,其内可见脂肪细胞、散在的淋巴细胞及肥大细胞等,门静脉管腔增大、血管内膜受损、内皮细胞脱落、中膜平滑肌增厚和血栓形成。与Sham组大鼠比较,CTPV组大鼠SOD、GSH-Px活性降低(93.79+8.87μU/L Vs103.05+8.07μU/L,P<0.05,157.44+26.46U/ml Vs709.09+83.21U/ml,P<0...     

两种介入途径治疗急性、亚急性门静脉及肠系膜上静脉血栓的临床疗效分析

目的：评价介入技术治疗急性和亚急性门静脉（portal vein,PV）及肠系膜上静脉（superior mesenterie vein, SMV）血栓形成的临床疗效。方法：对28例治疗急性和亚急性（发病一周至一月）的PV及SMV血栓患者进行介入治疗。按介入治疗途径不同分为下述两组：选择经颈静脉穿刺门静脉（transjugular intrahepatic portosystemic shunt , TIPS途径）置管溶栓（19例）和经皮穿肝内门脉（percutaneous transhepatic）置管溶栓治疗（9例）。结果：所有患者随访一周至三个月,其中治疗成功24例,临床症状明显改善,无严重并发症。经TIPS途径治疗的患者组中,16例随访显示大部分血栓被清除,门静脉系统有血流通过,临床症状缓解。3例SMV及PV恢复部分血流,但临床症状无明显改善。经皮穿肝内门脉直接置管溶栓治疗组中,6例患者的PV及SMV内血栓大部分清除,血流基本改善,2例患者PV及SMV血流部分好转,临床症状无明显改善,严重并发症1例（术后两天死于腹腔出血）。结论：经TIPS途径介入技术和经皮穿肝内门脉直接置管溶栓治疗是治疗急性和亚急性PV及SMV血栓形成的有效方法,前者的疗效及安全性均好于后者。     

两种介入途径治疗急性、亚急性门静脉及肠系膜上静脉血栓的临床疗效分析

目的:评价介入技术治疗急性和亚急性门静脉(portal vein,PV)及肠系膜上静脉(superior mesenteric vein,SMV)血栓形成的临床疗效。方法:对28例治疗急性和亚急性(发病一周至一月)的PV及SMV血栓患者进行介入治疗。按介入治疗途径不同分为下述两组:选择经颈静脉穿刺门静脉(transjugular intrahepatic portosystemic shunt,TIPS途径)置管溶栓(19例)和经皮穿肝内门脉(percutaneous transhepatic)置管溶栓治疗(9例)。结果:所有患者随访一周至三个月,其中治疗成功24例,临床症状明显改善,无严重并发症。经TIPS途径治疗的患者组中,16例随访显示大部分血栓被清除,门静脉系统有血流通过,临床症状缓解。3例SMV及PV恢复部分血流,但临床症状无明显改善。经皮穿肝内门脉直接置管溶栓治疗组中,6例患者的PV及SMV内血栓大部分清除,血流基本改善,2例患者PV及SMV血流部分好转,临床症状无明显改善,严重并发症1例(术后两天死于腹腔出血)。结论:经TIPS途径介入技术和经皮穿肝内门脉直接置管溶栓治疗是治疗急性和亚急性PV及SMV血栓形成的有效方法,前者的疗效及安全性均好于后者。