肝窦内皮细胞损伤和表型改变在大鼠肝硬化门脉高压发生中的作用

目的：探讨肝窦内皮细胞（SECs）损伤和表型改变与大鼠肝硬化门脉高压的关系。 方法： 采用二甲基亚硝胺（DMN）4周12次腹腔注射复制大鼠肝硬化模型，分别于造模后1 d、2 d、3 d、1周、2周、4周、6周、8周作动态观察；肠系膜前静脉分支插管法测门脉压力（Ppv）；透射电镜观察肝组织超微结构；免疫组化观察肝窦壁CD44和Ⅷ因子相关抗原（vWF）表达；Northern blot检测肝组织内皮素-1（ET-1） mRNA和内皮型一氧化氮合酶（eNOS）mRNA 表达；Western blot检测肝组织eNOS表达；放射免疫法测定血清透明质酸（HA）和肝组织ET-1含量。 结果： DMN造模1 d后CD44染色明显弱于正常对照组（P<0.05），SECs窗孔减少，血清HA含量显著高于正常对照组(P<0.05)；DMN造模2 d后vWF阳性染色明显强于正常对照组(P<0.05)；DMN大鼠的Ppv与肝窦壁vWF表达量和血清HA含量呈显著正相关(P<0.05)；造模2 d和3 d时ET-1 mRNA表达强于正常对照组，ET-1含量轻度高于正常对照组；造模1 d、2 d和3 d时eNOS mRNA表达强于正常对照组，而eNOS一直呈低水平状态。 结论：SECs损伤和表型改变是DMN大鼠肝硬化门脉高压形成的病理基础之一；ET-1和NO产生的平衡失调，使肝内血流阻力增加，在门脉高压形成过程中起重要作用。

Role of injury and phenotype shift of liver sinusoidal endothelial cells in the development of portal hypertension of cirrhosis in rats

AIM: To study the role of injury and phenotype shift of liver sinusoidal endothelial cells in the development of portal hypertension of liver cirrhosis in rats. METHODS: The rat liver cirrhosis model was established by peritoneal injection of dimethylnitrosamine (DMN) (at a dose of 10 mg·kg^-1, 3 times a week, for 4 weeks). The dynamic changes of liver cirrhosis were observed at different time points (1 day, 2 days, 3 days, 1 week, 2 weeks, 4 weeks, 6 weeks and 8 weeks). The pressure of portal vein (Ppv), the expression of CD44, von Willebrand factor (vWF), endothelin-1 (ET-1) mRNA and endothelial nitric oxide synthase (eNOS) mRNA, the serum hyaluronic acid (HA) content and liver ET-1 content were measured. RESULTS: Compared with the normal control rats, CD44 positive staining was weak in the 1 day model rats, and the numbers of fenestrae of sinusoidal endothelial cells (SECs) rapidly decreased, but serum HA content rapidly increased (P<0.05). vWF positive staining in the 2-day model rats was stronger than that in normal control rats (P<0.05). There was a positive correlation between the Ppv and the vWF expression, serum HA content in the DMN-induced liver cirrhosis rats (P<0.05). Compared with the normal control rats, ET-1 mRNA expression increased in the 2-day and 3-day model rats, and ET-1 content lightly increased. eNOS mRNA expression was stronger in the 1-day, 2-day and 3-day model rats than that in normal control rats, meanwhile eNOS always expressed at a low level. CONCLUSION: The injury and phenotype shift of SECs is a pathological basis in the development of portal hypertension of DMN-induced liver cirrhosis in rats. Imbalance of ET-1 and NO production increases intrahepatic resistance, which plays an important role in the development of portal hypertension.