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目的:探讨腺病毒介导的shRNA下调第10号染色体缺失的磷酸酶张力蛋白同源物基因（PTEN）表达对活化肝星状细胞（HSC）的纽蛋白（vinculin）、细丝蛋白A（filamin A）及皮层肌动蛋白（cortactin）的影响。方法:体外培养活化大鼠肝星状细胞系HSC-T6，将携带靶向PTEN的RNA干扰序列[短发夹RNA（short hairpin RNA, shRNA）]的重组腺病毒Ad-shRNA/PTEN及对照空病毒Ad-GFP转染HSC；采用实时荧光定量PCR及Western blot技术检测各组HSC的PTEN mRNA及蛋白表达；借助激光扫描共聚焦显微镜，采用免疫荧光法检测各组HSC的vinculin、filamin A及cortactin表达变化，并利用Image-pro plus 6.0软件进行图像分析处理，计算所测蛋白荧光表达的积分光密度值（IOD）。实验分为3组：对照组（在腺病毒转染步骤以DMEM代替腺病毒液）、Ad-GFP组（转染仅表达绿色荧光蛋白的空病毒Ad-GFP）、Ad-shRNA/PTEN组（转染携带靶向PTEN的shRNA并表达绿色荧光蛋白的重组腺病毒Ad-shRNA/PTEN）。3组间均数比较采用单因素方差分析，组间比较采用LSD检验。结果:靶向PTEN的shRNA成功转染并显著下调HSC的PTEN mRNA及蛋白表达（n P 0.05），但3组HSC的filamin A亚细胞分布发生了变化，Ad-shRNA/PTEN组HSC的filamin A主要分布于细胞质，而对照组和Ad-GFP组HSC的filamin A主要位于细胞核，Ad-shRNA/PTEN组HSC的filamin A核质比（0.60±0.15）明显低于对照组（1.20±0.15）及Ad-GFP组（1.08±0.23）， n P 0.05）。3组HSC的cortactin主要分布于细胞质，Ad-shRNA/PTEN组HSC的cortactin荧光IOD（54 688.50±2 095.53）较对照组（22 959.94±1 710.42 ）及Ad-GFP组（22 547.11±1 588.72）显著升高（ n P 0.05）。n 结论:PTEN表达下调使体外活化肝星状细胞的微丝结合蛋白vinculin及cortactin的表达上调，并使另一微丝结合蛋白filamin A的亚细胞分布发生改变即出现胞核向细胞质转位。“,”Objective:To investigate the effect of adenovirus-mediated shRNA down-regulating phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression on vinculin, filamin A, and cortactin in activated hepatic stellate cells (HSCs).Methods:Activated rats hepatic stellate cell line (HSC-T6) was cultured in vitro. Recombinant adenovirus Ad-shRNA/PTEN carrying PTEN targeted RNA interference sequence [short hairpin RNA (shRNA)] and empty control virus Ad-GFP were transfected into HSCs. The PTEN mRNA and protein expression of HSCs in each group were detected by real-time fluorescence quantitative PCR and Western blot. The expressional change of vinculin, filamin A and cortactin in HSCs of each group were detected by confocal laser scanning immunofluorescence microscope. Image-pro plus 6.0 software was used for image analysis and processing. The integrated optical density (IOD) of the fluorescence protein expression was measured. The experiment was divided into three groups: control group (DMEM instead of adenovirus solution in the adenovirus transfection step), Ad-GFP group (transfected with empty virus Ad-GFP only expressing green fluorescent protein), and Ad-shRNA/PTEN group (recombinant adenovirus Ad-shRNA/PTEN carrying shRNA targeting PTEN and expressing green fluorescent protein). One-way analysis of variance was used for comparison of mean value among the three groups, and LSD-test was used for comparison between the groups.Results:shRNA targeted PTEN was successfully transfected and the expression of PTEN mRNA and protein in HSC (n P 0.05), but the subcellular distribution of Filamin A among the three groups were changed. Filamin A in the Ad-shrNA /PTEN HSC group was mainly distributed in the cytoplasm. Filamin A HSC was mainly located in the nucleus.The filamin A HSC in the control group and Ad-GFP group was mainly located in the nucleus. The nucleocytoplasmic ratio of Filamin A in the AD-shrNA /PTEN group (0.60 ± 0.15) was significantly lower than control group (1.20 ± 0.15) and Ad-GFP group (1.08 ± 0.23), n P 0.05). Cortactin HSCs in the three groups was mainly distributed in the cytoplasm. The cortactin fluorescence IOD of HSCs in the Ad-shRNA/PTEN group was significantly higher than control group (22 959.94 ± 1 710.42) and the Ad-GFP group (22 547.11 ± 1 588.72 ) ( n P 0.05).n Conclusion:The down-regulation of PTEN expression raises the expression of microfilament-binding protein vinculin and cortactin, and changes the subcellular distribution of another microfilament binding protein filamin A, that is, translocation from nucleus to the cytoplasm in activated HSC in vitro.