可恢复性肝外门静脉高压动物模型的建立及其实验研究

目的探讨采用套管将门静脉主干部分缩窄后再去除的方法制作一种可恢复性肝外门静脉高压动物模型的可行性及有效性。方法将18只新西兰大白兔按随机数字表法分为三组,每组6只:对照组(normal control group,NC)、肝外门静脉高压组(extra-hepatic portal venous obstruction,EHPVO)和可恢复性肝外门静脉高压组(reversible extra-hepatic portal venous obstruction,r-EHPVO)。NC组仅开腹后游离门静脉主干。EHPVO组采用套管将门静脉主干部分缩窄制作肝外门静脉高压动物模型。r-EHPVO组在肝外门静脉高压模型制备2周后将套管去除。检测所有动物模型手术前后的门静脉压力、血常规和脾脏大小,并比较各组手术前后门静脉压力、红细胞、白细胞、血红蛋白及血小板和脾脏大小的变化。多组间比较采用单因素方差分析(one-way ANOVA),同一组不同时间段间的数据比较采用配对样本的t检验,以P<0.05为差异有统计学意义。结果18只动物模型的制作均成功完成。EHPVO组和r-EHPVO组的术后门静脉压力和脾脏大小均显著高于NC组,差异有统计学意义(P<0.01);EHPVO组与r-EHPVO组套管拆除前门静脉压力和脾脏大小比较,差异无统计学意义;套管拆除后r-EHPVO组门静脉压力和脾脏大小显著低于EHPVO组,但其仍高于NC组(P<0.01)。EHPVO组和r-EHPVO组的术后血红蛋白、红细胞和血小板均显著低于NC组(P<0.05);去除套管后,r-EHPVO组血红蛋白、红细胞和血小板显著高于EHPVO组,但仍低于NC组。结论采用套管将门静脉主干部分缩窄后再去除的方法制作可恢复性肝外门静脉高压动物模型是可行的,该动物模型可缓解门静脉高压状态(降低门静脉压力、脾脏大小和改善脾功能亢进状态),具有Rex手术治疗肝外门静脉高压的相似效果,能作为模拟Rex手术研究的动物模型。

An experimental study for animal model of reversible extrahepatic portal hypertension

Objective To explore the feasibility and effectiveness of establishing a reversible animal model for extrahepatic portal hypertension by removing a tubed narrowing of major portal vein.Methods Eighteen New Zealand white rabbits were randomly divided into three groups of control(NC),extra-hepatic portal hypertension(EHPVO)and recoverable extra-hepatic portal hypertension(r-EHPVO)(n=6 each).In NC group,only major portal vein was mobilized after laparotomy.In EHPVO group,animal model of extrahepatic portal hypertension was made by narrowing major portal vein using a cannula.And r-EHPVO extrahepatic portal hypertension model was prepared and a cannula removed 2 weeks later.Portal venous pressure,blood routine and splenic size were measured before and after operation in all animal models and the changes of portal venous pressure,red blood cell,white blood cell,hemoglobin,platelets and splenic size pre/post-operation in each group were compared.One-way analysis of variance(one-way ANOVA)was utilized for comparing multiple groups and t-test for paired samples for comparing the data between different timepoints in the same group.P<0.05 was considered statistically significant.Results All 18 animal models were successfully completed.The postoperative portal venous pressure and splenic size were significantly higher in EHPVO and r-EHPVO groups than those in NC group and the differences were statistically significant(P<0.01);no significant difference existed in portal venous pressure or splenic size before cannula removal in EHPVO/r-EHPVO group;portal venous pressure and splenic size were significantly lower in r-EHPVO group than those in EHPVO group after cannula removal,yet higher than those in NC group(P<0.01).Postoperative hemoglobin,red blood cell and platelet were significantly lower in r-EHPVO group than those in NC group(P<0.05);after removing cannula,hemoglobin,red blood cell and platelet were significantly higher in r-EHPVO group than those in EHPVO group,yet still lower than those in NC group.Conclusions It is feasible to make a reversible animal model of extrahepatic portal hypertension by removing a tubed narrowing of major portal vein.In this animal model,the symptoms of portal hypertension were relieved.It has the similar effect of Rex shunt for treating extrahepatic portal hypertension.