Xu Ke-Shu, Li Qi, Zhou Xia
Department of Gastroenterology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Zhonghua Gan Zang Bing Za Zhi. 2006 Oct;14(10):753-6.
To explore the quantity of mast cells and the role of protease activated receptor-2 (PAR-2) in experimental rat liver fibrosis.
Rats were sacrificed at 0, 2, 4, 8, and 12 weeks after subcutaneous injection of CCl(4). Mast cells were displayed by toluidine blue stain. The content of liver hydroxyproline was measured by the method of base hydrolyzate. The mRNA expression and the protein expression of PAR-2 in livers were detected by RT-PCR and immunohistochemistry at each time point.
In normal rat livers there were a few mast cells (2.5+/-1.0) distributed along the hepatic portal areas. In the cirrhosis model group the number of mast cells in the livers increased degree by degree (2 weeks vs 4 weeks vs 8 weeks, 9.1+/-0.5 vs 15.7+/-3.0 vs 32.0+/-3.3; P less than 0.05), and they were distributed densely around the hepatic portal areas and the central veins. The content of liver hydroxyproline increased progressively from 0 to 12 weeks. In normal livers PAR-2 mRNA was hardly detected, at 2 weeks there was some expression of PAR-2 mRNA (PAR-2/beta-actin 0.15+/-0.01, P less than 0.05), at 4 weeks its expression increased (PAR-2/beta-actin 0.35+/-0.02, P less than 0.05) and it maintained a higher level (PAR-2/beta-actin 0.80+/-0.02, P less than 0.05) since then. The changing trend of the protein expression of PAR-2 was the same as that of PAR-2 mRNA expression.
PAR-2 mRNA expression and the protein expression of PAR-2 were consistent with the increase of the mast cells, and the content of liver hydroxyproline may play an important role in mediating liver fibrosis.
探讨实验性大鼠肝纤维化中肥大细胞数量及蛋白酶激活受体-2（PAR-2）的作用。
于皮下注射四氯化碳后0、2、4、8和12周处死大鼠。用甲苯胺蓝染色显示肥大细胞。采用碱水解法测定肝脏羟脯氨酸含量。在每个时间点通过逆转录聚合酶链反应（RT-PCR）和免疫组织化学检测肝脏中PAR-2的mRNA表达和蛋白表达。
正常大鼠肝脏中沿肝门区分布有少量肥大细胞（2.5±1.0）。在肝硬化模型组，肝脏中肥大细胞数量逐渐增加（2周与4周与8周比较，9.1±0.5与15.7±3.0与32.0±3.3；P<0.05），且密集分布于肝门区和中央静脉周围。肝脏羟脯氨酸含量从0至12周逐渐增加。正常肝脏中几乎检测不到PAR-2 mRNA，2周时有PAR-2 mRNA的一些表达（PAR-2/β-肌动蛋白0.15±0.01，P<0.05），4周时其表达增加（PAR-2/β-肌动蛋白0.35±0.02，P<0.05），此后维持在较高水平（PAR-2/β-肌动蛋白0.80±0.02，P<0.05）。PAR-2蛋白表达的变化趋势与PAR-2 mRNA表达相同。
PAR-2 mRNA表达和PAR-2蛋白表达与肥大细胞数量增加一致，肝脏羟脯氨酸含量可能在介导肝纤维化中起重要作用。
