PLATELET ACCUMULATION IN THE REMNANT LIVER AFTER PARTIAL HEPATECTOMY : THE ROLE OF PLATELETS IN LIVER REGENERATION

背景和目的。我们评估了肝部分切除后血小板在肝脏中的聚集水平，并检测了血小板在肝脏再生中的作用。材料和方法。我们在小鼠身上进行了70%的肝部分切除。按治疗方法分为HX组、KD组、TP组，HX组注射生理盐水，KD组注射二氯亚甲基双膦酸脂质体去除Kupffer细胞，TP组注射抗血小板抗体造成严重的血小板减少。通过组织化学观察和检测肝脏中存在的血小板中的5-羟色胺含量来评估血小板移位。用增殖细胞核抗原标记指数和肝/体重比检测肝再生情况。抗血小板组织化学染色显示肝部分切除后HX组大鼠肝脏内有大量的血小板聚集，KD组和TP组未见。KD组和TP组大鼠肝脏5-羟色胺无明显变化。在肝切除后36小时，KD组和TP组的增殖细胞核抗原标记指数分别为18.9[-+]8.1和28.1[-+]7.1%，明显低于HX组(42.0[-+]7.6)。与HX组相比，KD组和TP组大鼠肝切除后肝/体重恢复较慢。本研究提示Kupffer细胞在肝切除后可诱导血小板移位至肝脏，而聚集的血小板在肝脏再生中起重要作用。

Background and Aim. We evaluate the level of platelets accumulation in liver after partial hepatectomy and examined the role of platelets in liver regeneration.Materials and Methods. We performed 70% partial hepatectomy in mice. The mice divided into three groups by treatment ; Hx group was control injected with saline, Kd group was depleted kupffer cells by administration of liposome encapsulating dichloromethylene bisphosphonate, Tp group was given anti-platelet antibody with resulting severe thrombocytepenia. Translocation of platelets was assessed by histochemical findings and measuring 5-hydroxytryptamine contained in platelets which were existed in liver. Liver regeneration was examined by PCNA labeling index and liver/body weight ratio.Results. Anti-platelet histochemical staining revealed accumulation of many platelets in the liver of Hx group after partial hepatectomy, but not in Kd and Tp groups. Hepatic 5-hydroxytryptamine of Kd and Tp groups did not changed. At the time of 36hr after hepatectomy, PCNA labeling indexes of Kd and Tp groups, in which platelets did not participate in the liver, were 18.9【minus-plus】8.1 and 28.1【minus-plus】7.1% respectively, and those were markedly lower than that of Hx group (42.0【minus-plus】7.6). Restoration of liver/body weight ratio after hepatectomy were retarded in Kd and Tp groups compared to Hx group.Conclusion. This study suggests that kupffer cells induce the translocation of platelets to the liver after hepatectomy and that accumulating platelets play an important role in liver regeneration.