异环磷酰胺对离体大鼠肝细胞毒作用机制研究

Study on toxicity mechanism(s) of ifosfamide in suspending cultured rat hepatocytes

目的 :探讨异环磷酰胺 (Ifo)对混悬培养大鼠肝细胞的毒性效应及其可能机制。方法 :以两步灌流法消化成年大鼠肝细胞 ,并进行混悬培养。Ifo以 5,10 ,2 0mmol/L染毒 ,观察染毒后 3h肝细胞的存活率、胞内酶泄漏情况以及肝细胞巯基状态、丙二醛 (MDA)含量的变化 ,并对肝细胞表面形态和超微结构进行观察。结果 :随着染毒浓度的增大 ,肝细胞存活率逐渐下降 ,胞内酶泄漏加重 ,培养液中乳酸脱氢酶 (LDH)、天冬氨酸氨基转移酶 (AST)活性增高 ,同时肝细胞总巯基 (TSH)、非蛋白巯基 (NPSH)、蛋白巯基 (PSH)也逐渐下降 ,其中PSH下降在TSH耗竭中起主要作用。肝细胞MDA含量未发现有显著增高。形态学检查发现Ifo使肝细胞表面出现“大疱” ,胞内线粒体肿胀 ,空泡化 ,粗面内质网扩张 ,部分脱颗粒 ,内腔模糊 ,滑面内质网扩张 ,呈囊泡状改变。结论 :Ifo对混悬培养大鼠肝细胞有损伤作用 。

Objective:To study the toxicity mechanism(s) of ifosfamide(Ifo) in suspending cultured rat hepatocytes.Methods:Hepatocytes of adult rat were isolated using two step perfusion method and cultured suspendingly. Cell viability,intracellular enzyme leakage, contents of sulfhydryl groups and MDA contents of hepatocytes were examined 3 hours after ifosfamide was administered at 5,10,20 mmol/L. Surface and ultrastructure of hepatocytes were also observed. Results:Cell viability and TSH,NPSH,PSH contents of hepatocytes significantly declined, and LDH,AST activities in media increased due to the leakage of intracellular enzymes. The decrease in PSH content was ascribed to depletion of TSH. The higher the dose was, the more serious these changes became. However, MDA contents of the hepatocytes were not found increased at any ifo dose groups. In pathological examination, “bulla' formation was found on the surface of the hepatocytes, deformation,swelling even vacuolation of mitochondria and dilation of rough,smooth endoplasmic reticulum were also observed. Conclusions:Ifo has toxic effect on suspending cultured rat hepatocytes. The decrease in sulfhydryl groups contributes to the hepatotoxicity induced by Ifo. [