Retrorsine对小鼠肝损伤后肝细胞增殖的影响

Influences of retrorsine on mouse hepatocyte proliferation after liver injury

目的:比较倒千里光碱(retrorsine)对小鼠与大鼠肝损伤后肝细胞增殖的影响,探讨应用retrorsine建立小鼠肝细胞移植模型的可行性。方法:雄性小鼠和大鼠均各自分为retrorsine处理组和生理盐水注射组(未处理组),每组30只。Retrorsine处理组动物分别接受2次(间隔2周)retrorsine注射(小鼠剂量为70 mg/kg,大鼠剂量为30 mg/kg);未处理组用生理盐水代替retrors-ine。末次注射4周后,所有的动物均予CCl4注射(0.5 mg/kg),分别在CCl4注射前即刻(记为0时)、注射后第1、2、3、4、6和15天取动物肝组织样本。H-E染色检查动物肝组织病理学变化,Ki-67染色检测动物肝细胞增殖情况。结果:H-E染色发现retrors-ine处理组大鼠肝组织出现明显的巨细胞增多、小胆管增生和小肝细胞增生并形成结节,而未处理组大鼠未出现这些表现,两组间有显著差异;然而,retrorsine处理组及未处理组小鼠肝组织均表现为肝细胞变性、肝小叶中央静脉周围区坏死,未出现巨细胞增生,两组表现类似。Retrorsine处理组大鼠Ki-67染色阳性肝细胞主要出现在小肝细胞结节中,CCl4注射后第3天Ki-67染色阳性肝细胞数明显少于未处理组(P<0.05);而retrorsine处理组小鼠Ki-67阳性细胞计数几乎在各时间点均高于未处理组,尤其在CCl4注射后第4天(P<0.001),两组变化趋势一致。结论:应用retrorsine可明显抑制大鼠肝损伤后肝细胞增殖,适用于建立大鼠肝细胞移植模型;retrorsine对小鼠肝损伤后肝细胞增殖无明显抑制作用,不适用于建立小鼠肝细胞移植模型。

Objective： To compare the influences of retrorsine on hepatocytes proliferation in mice and rats after liver injury, so as to investigate the feasibility of using retrorsine for establishment of liver cell transplantation model in mice. Methods： Male mice and rats were pretreated with 2 injections of retrorsine （70 mg/kg for mice and 30 mg/kg for rats） （as retrorsine-treated group, n=30） at 2 weeks interval or saline （as non treated group, n： 30）. A single injection of carbon tetrachloride （CCl4 , 0.5 mg/kg） was given to all animals 4 weeks after the final injection of retrorsine or saline. At 0（before administration）, 1, 2, 3, 4, 6, 15 d after CCl4 administration, the animals were sacrificed and their livers were subjected to H-E staining and Ki-67 antibody immunohistochemistry analysis to evaluate the pathological changes and hepatocyte proliferation. Results： The liver in rats treated with retrorsine displayed obvious megalocytosis, small bile duct hyperplasia, and small hepatocyte hyperplasia （forming nodule） ; no such changes were found in non-treated group. However, the liver in mice treated with retrorsine displayed hepatocyte degeneration and necrosis in the perivenous areas and the same was true to the liver in non-treated mice. Ki-67 immunohistochemistry analysis showed that in rats treated with retrorsine, the positive hepatocytes, mainly found in small hepatocyte nodules, were obviously less than those in control group 3 d after CCl4 administration（P〈0.05）. Ki-67 positive hepatocytes in mice treated with retrorsine were abundant and almost more than those in control group at all time points, especially 4 d after CCl4 administration（P〈0.01 ）, with the same changing tendency in both groups. Conclusion： Retrorsine can obviously inhibit hepatocyte proliferation after liver injury and is suitable for liver cell transplantation in rats,while it is the contrary in mice.