摘要
目的:探讨γ-氨基丁酸(GABA)B受体在肝纤维化大鼠中的表达.方法:SD大鼠,腹腔注射50%CCl4制备大鼠肝纤维化模型.从第6周开始,每周1次取大鼠肝组织,得到不同肝纤维化程度的肝脏标本.一部分标本40g/L甲醛固定,常规石蜡包埋,连续4μm切片,做组织病理学染色(HE、Masson)和免疫组织化学(α-SMA),以确定不同肝纤维化水平.另一部分标本-80℃保存用于提取肝脏RNA,逆转录得到cDNA,设计GABA(B)受体、α-SMA、TGF-β、胶原Ⅰ、胶原Ⅲ的引物,做实时荧光定量PCR,分析GABA(B)受体的表达与大鼠肝纤维化程度的相关性.结果:建模7wk时,α-SMA、TGF-β、胶原Ⅰ和胶原Ⅲ较6wk分别增加19.2倍、2.1倍、37.5倍和183.5倍.GABA(B)受体基因表达也明显升高,升高量达到116.2倍.6wk对照组GABA(B)受体基因表达是模型组的2倍.到12wk初步形成假小叶时,只有α-SMA和胶原Ⅰ增加显著,分别为21.6倍和20.1倍.TGF-β和胶原Ⅲ变化不明显.其他时间点基因表达与6wk模型相比无明显变化.结论:GABA(B)受体可能参与了肝纤维化的发生.在肝纤维化晚期,细胞外基质的合成主要以胶原Ⅰ为主,胶原Ⅲ次之.α-SMA的表达与肝纤维化水平呈正相关.
AIM： To investigate the expression of γ-aminobutyric acid （GABA） B receptor in carbon tetrachloride-induced liver fibrosis in rats.METHODS： Male Sprague-Dawley rats were intraperitoneally injected with 50% carbon tetrachloride to induce liver fibrosis. Six weeks after induction, liver tissue samples were taken once a week. Each sample was divided into two parts： one was used for hematoxylin and eosin and Masson＇s trichrome staining to assess the degree of liver fibrosis and imrnunohistochemistry to determine the level of m-smooth muscle actin （α-SMA）, the other was used for real-time reverse transcription-polymerase chain reaction to detect the expression of GABA B receptor, α-SMA, transforming growth factor-β（TGF-β）, collagen I and collagen III mRNAs.RESULTS： The expression levels of α-SMA, TGF-β, collagen I, collagen III and GABA（B） receptor mRNAs in liver fibrosis at week 7 increased 19.2, 2.1, 37.5, 183.5 and 116.2 times as much as those at week 6, the expression level 6, respectively. At week of GABA（B） receptor in the liver in rats with liver fibrosis was reduced by two times when compared with that in normal control rats. At week 12 when pseudolobule formed, the expression levels of α-SMA and collagen I mRNAs increased 21.6 and 20.6 times as much as those at week 6, respectively, while those of TGF-β and collagen Ⅲ mRNAs showed no obvious changes. The expression levels of these genes at other time points were almost unchanged when compared with those at week 6.CONCLUSION： GABA（B） receptor may be involved.in the progression of liver fibrosis. In advanced liver fibrosis, the extracellular matrix synthesized is mainly collagen I. The expression of α-SMA is positively correlated with the degree of liver fibrosis.
出处
《世界华人消化杂志》
CAS
北大核心
2009年第25期2555-2560,共6页
World Chinese Journal of Digestology
基金
国家自然科学基金资助项目
No.30800509~~
