硫化氢对大鼠肝纤维化的抑制作用及机制探讨

目的观察外源性硫化氢（H2S）对四氯化碳（CCl4）诱导大鼠肝纤维化的抑制作用，并探讨其机制。方法将50只雄性SD大鼠随机分为5组，空白对照组皮下注射花生油2．0mL／kg体质量，肝纤维化组注射同剂量40％CCL4花生油，NailS低剂量组注射同剂量40％CCL4花生油＋NailS7μmol／kg，NailS高剂量组注射同剂量40％CCL4花生油＋NariS14μmol／kg，秋水仙碱组注射相同剂量40％CCL4花生油＋秋水仙碱0．25mg／kg灌胃，每周2次，共8周。采用全自动生化检测仪检测各组大鼠血清ALT、AST，放射免疫法检测肝脏组织透明质酸（HA）、层黏连蛋白（LN）、Ⅲ型前胶原（PCⅢ）及Ⅳ型胶原（CⅣ），羟胺法检测肝组织超氧化物歧化酶（SOD），比色法检测肝组织丙二醛（MDA）和谷胱甘肽过氧化酶（GSH—Px），HE染色观察肝组织学改变，网状纤维和masson染色观察肝纤维组织增生状况，免疫组化法检测肝组织I型、Ⅲ型胶原。结果与空白对照组比较，肝纤维化组ALT、AST、HA、LN、PCⅢ、CIV、MDA升高，SOD、GSH—Px降低（P均〈0．05）；与肝纤维化组比较，NariS低剂量组、NaHS高剂量组、秋水仙碱组ALT、AST、HA、LN、PCⅢ、CIV、MDA降低，SOD、GSH—Px升高（P均〈0．05）。与肝纤维化组比较，NaHS低剂量组、NaHS高剂量组、秋水仙碱组肝纤维化程度减轻，肝组织胶原纤维异常分布明显减少，I型、Ⅲ型胶原明显减少。结论外源性H，S能有效抑制大鼠肝纤维化的发生、发展，其机制可能与其清除自由基、提高抗氧化物酶的活性、抑制HSC的胶原合成、减少细胞外基质在肝脏中的沉积有关。

Inhibitory effect of hydrogen sulfide on liver fibrosis in rats and its mechanism

Objective To observe the inhibitive effect of hydrogen sulfide on liver fibrosis in rats and to discuss its mechanism of action. Methods Fifty male rats were randomly divided into 5 groups ： the blank control group with subcuta- neous injection of peanut oil 2.0 mL/kg, liver fibrosis group which was injected with the same dose of 40% CCL4 peanut oil, low dose NariS group which was injected with the same dose of 40% CCL4 peanut oil ＋ NariS 7 μmol/kg, high dose NariS group which was injected with the same dose of 40% CCL4 peanut oil ＋ NariS 14 μmol/kg, and the colchicine group which was injected with the same dose of 40% CCL4 peanut oil ＋ 0.25 mg/kg colchieine. All rats except those in the con- trol group were subcutaneously injected with CCIA twice a week for 8 weeks to test liver fibrosis. The activities of transami- nase in serum, malondiadehyde （MDA） content, superoxide dismutase （SOD）, and glutathione peroxidase （GSH-Px） ac- tivities in liver homogenate were assayed, and levels of serum hyaluronic acid （HA）, laminin （LN）, collegen type Ⅳ （C Ⅳ ）, procollagen Ⅲ （PC Ⅲ ） were tested. The pathological changes of liver were observed by HE, reticular fiber and Mas- son stain. The expression of type I and type Ⅲ collagen was detected by immunohistochemical method. Results The re- suits showed that the serum ALT and AST decreased by NariS treatment. Pathological examination showed that H2 S could remarkably alleviate the hepatic fibrosis. H2S not only decreased the HA and LC content in liver homogenates,but also ele- vated the levels of PC Ⅲ and C IV in serum. H2 S also ameliorated the oxidative stress state of hepatic fibrosis rats, decreased the production of MDA and enhanced the activities of antioxidative enzyme including SOD and GSH-Px （ all P 〈 0.05 ）. Conclusions H2S has protective effect on liver fibrosis rats induced by CCL4. The mechanisms of anti-fibrotic effects may be associated with its action of ameliorating the oxidative stress in liver and inhibiting the production of collagen in HSC.