Ⅳ型胶原酶门脉灌注对兔肝硬化组织中ɑ-平滑肌动蛋白的影响

Effect of expression of α-SMA in liver cirrhosis by portal type Ⅳ collagenase administration

目的四氯化碳(CC l4)皮下注射建立兔肝硬化动物模型,观察Ⅳ型胶原酶门脉灌注对肝硬化组织中α-平滑肌动蛋白(α-SMA)表达的影响。方法取雄性新西兰大白兔,采用臀部皮下注射50%CC l4橄榄油0.23 mL/kg,每周2次,共12周制作肝硬化动物模型,注射等量橄榄油作为对照。12周后各组动物均建立门静脉给药通路,将已形成肝硬化并门静脉插管成功的33只兔随机分为两组(组1,组2),组1有16只、组2有17只。组1经门静脉给药通路注入0.1%Ⅳ型胶原酶1.5 mL,组2注入等量0.9%NaC l,5次/周,共4周。将造模对照组中门静脉插管成功的30只兔同样随机分为两组(组3,组4),每组15只,处理方法同前。4周后,将各组动物处死后留取肝脏组织,固定后α-SMA免疫组织化学染色,行积分光密度、面密度分析。结果肝硬化动物肝脏α-SMA表达显著增强;门脉灌注0.1%Ⅳ型胶原酶肝硬化动物肝脏纤维化程度明显降低,但α-SMA表达强度显著增高。结论采用门脉灌注0.1%Ⅳ型胶原酶可显著增高α-SMA表达,可能与肝脏肝星状细胞激活有关。

Objective To investigate the effect of portal type Ⅳ collagenase administration on expression of α-SMA in cirrhotic liver induced by CCl4 subcutaneous injections in rabbits. Methods Male New Zealand rabbits were injected 0.23 mL of 50% CCl4/olive oil subcutaneously at gluteal region twice a week for 12 weeks to induce liver cirrhosis.The animals in control group administered same volumes of olive oil.After the portal delivery system（PDS） was established,33 rabbits which were successfully induced liver cirrhosis were randomly divided into 2 groups.The animals in group 1（n=16） were injected 1.5 mL of 0.1% type Ⅳ collagenase saline solution through PDS.The rabbits in group 2（n=17） received the same volume of 0.9% NaCl as controls.The injection was conducted 5 times a week and continued for 4 weeks.Another 30 animals which were injected with olive oil only were divided into group 3（n=15） and group 4（n=15）,they underwent the same procedure.All animals were sacrificed after the last injection,and the livers were removed to detect the expression of α-SMA by immunohistochemistry.The integral optical density and area density were calculated by an imaging analysis system. Results The expression of α-SMA in the cirrhotic liver remarkedly increased.Portal administration of type Ⅳ collagenase significantly attenuated liver cirrhosis,but the expression of α-SMA increased in liver parenchyma. Conclusion Collagenase portal administration significantly increased the expression of αSMA in liver.This may attribute to the enhanced activation of hepatic stellate cells by collagenase treatment.