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目的了解激活的HSC中c－myb及肝脏组织特异的转录因子－肝脏激活蛋白（liveractivatorprotein，LAP）在α1（Ⅰ）基因表达调控中的作用。方法采用链霉蛋白酶，胶原酶原位灌注、Nycodenz密度梯度离心分离大鼠HSC，并进行体外培养使之激活。构建含人α1（Ⅰ）胶原基因启动子片段（－804～＋1452或－804～＋222碱基）的荧光素酶报告基因质粒。用构建的报告基因质粒与c－myb和（或）LAP表达质粒一起，用阳离子脂质体介导的方法，瞬时共转染激活的HSC。结果瞬时共转染LAP表达质粒可明显增强含α1（Ⅰ）基因第一内含子片段的荧光素酶报告基因（PGL_3－col）及不含α1（Ⅰ）基因第一内含子的报告基因［PGL_3－col（△intron）］报告基因在HSC中的表达［荧光素酶活性分别为每毫克蛋白（587±62）U对（315±45）U及（326±52）U对（220±70）U，t值分别为10.4和3.6,两者P值均小于0.05］。C－myb对这两个报告基因均无反式激活作用。但共转染c－myb及LAP表达质粒，即使PGL_3－col报告基因在HSC中的表达增强近3倍［每毫克蛋白（1261±130）U对（315±45）U，t＝ 20．6，P＜0.01］，而共转染反义C－myb及LAP表达质粒，却抑制了LAP对α1（Ⅰ）基因启动子的反式激活作用［每毫克蛋白（334±29）U对（315±45）U，t＝1.
Objective To investigate the role of c-myb and liver tissue-specific transcription factor-live activator protein (LAP) in the regulation of α1 (Ⅰ) gene expression in activated HSC. Methods The rat HSCs were isolated by pronase injection of streptavidin, collagenase and Nycodenz density gradient centrifugation, and then cultured in vitro to activate them. A luciferase reporter plasmid containing the human α1 (Ⅰ) collagen gene promoter fragment (-804 to +1452 or -804 to +222 bases) was constructed. The constructed reporter plasmids were transiently co-transfected with activated HSCs using cationic liposome-mediated methods along with c-myb and / or LAP expression plasmids. Results Transient co-transfection of LAP expression plasmids significantly enhanced the luciferase reporter gene (PGL_3-col) containing the first intron of α1 (Ⅰ) gene and the reporter gene without α1 (Ⅰ) first intron [PGL_3-col (Δintron)] reporter gene expression in HSCs [luciferase activity was 587 ± 62 U / (315 ± 45) U and (326 ± 52) U vs 220 ± 70) U, t values were 10.4 and 3.6, respectively, both P values less than 0.05]. C-myb has no transactivation effect on both reporter genes. However, c-myb and LAP expression plasmids were co-transfected, even though the expression of the PGL_3-col reporter gene was nearly 3-fold increased in HSCs [1261 ± 130 U per milliliter (315 ± 45) U vs. t = 20.6 , P <0.01]. However, co-transfection of antisense C-myb and LAP expression plasmids inhibited the transactivation effect of LAP on α1 (Ⅰ) gene promoter [334 ± 29 U per milligram ± 45) U, t = 1.