Mancini R, Jezequel A M, Benedetti A, Paolucci F, Trozzi L, Orlandi F
Department of Gastroenterology, University of Ancona, Italy.
J Hepatol. 1992 Jul;15(3):361-6. doi: 10.1016/0168-8278(92)90069-2.
Proliferating lipocytes (fat-storing cells or perisinusoidal stellate cells of the liver) were detected by in vivo incorporation of bromodeoxyuridine (BrdU) in an experimental model of cirrhosis in the rat by dimethylnitrosamine. Lipocytes were identified by sequential double immunohistochemical staining on frozen sections using anti-desmin antibodies as a marker of cytoplasmic intermediate filaments followed by anti-BrdU antibodies to identify S-phase nuclei in animals treated for 7, 14 or 21 days. The number of desmin-positive (lipocytes) and desmin-negative (Kupffer and endothelial cells) sinusoidal cells incorporating BrdU was recorded. The labelling index of lipocytes was calculated as the percentage of BrdU-labelled desmin-positive cells with respect to total number of lipocytes. In control animals, when the total number of lipocytes was 153.9 +/- 11/mm2 (mean +/- 1 S.E.) the number of desmin-positive S-phase sinusoidal cells never exceeded 6.8 +/- 1.2/mm2 with a maximum labelling index of 4.3 +/- 0.5%. At 7 days of treatment, the values were respectively 236 +/- 26.5/mm2, 53.2 +/- 5.9/mm2 and 22.6 +/- 0.5% (p less than 0.001 vs. controls), while, at 21 days they were 272.5 +/- 21.2/mm2, 23.3 +/- 4.0/mm2 and 8.5 +/- 1.1% respectively (p less than 0.01). These results show that hyperplasia of lipocytes represents an early reaction to dimethylnitrosamine-induced liver injury. The local accumulation of lipocytes appears to occur in areas where fibrous septa develop later on.
在二甲基亚硝胺诱导的大鼠肝硬化实验模型中，通过体内掺入溴脱氧尿苷（BrdU）来检测增殖的脂肪细胞（肝脏的脂肪储存细胞或肝血窦周星状细胞）。在冷冻切片上，使用抗结蛋白抗体作为细胞质中间丝的标志物，随后用抗BrdU抗体来鉴定处于S期细胞核，通过连续双重免疫组织化学染色来识别脂肪细胞，这些动物分别接受了7天、14天或21天的治疗。记录掺入BrdU的结蛋白阳性（脂肪细胞）和结蛋白阴性（库普弗细胞和内皮细胞）的肝血窦细胞数量。脂肪细胞的标记指数计算为BrdU标记的结蛋白阳性细胞数占脂肪细胞总数的百分比。在对照动物中，当脂肪细胞总数为153.9±11/mm²（平均值±1个标准误）时，结蛋白阳性的S期肝血窦细胞数从未超过6.8±1.2/mm²，最大标记指数为4.3±0.5%。在治疗7天时，相应的值分别为236±26.5/mm²、53.2±5.9/mm²和22.6±0.5%（与对照组相比，p＜0.001），而在21天时，它们分别为272.5±21.2/mm²、23.3±4.0/mm²和8.5±1.1%（p＜0.01）。这些结果表明，脂肪细胞增生是对二甲基亚硝胺诱导的肝损伤的早期反应。脂肪细胞的局部积聚似乎发生在随后形成纤维间隔的区域。
