摘要
本文应用核苷掺入技术及电镜观察首次证实雷公藤内酯对人胃癌细胞株 FGC_(85)的杀伤作用。用药早期,细胞数,分裂指数及 DNA,RNA 合成无明显变化,但出现核仁脱粒及核仁破碎等变化;晚期,电镜观察发现细胞以凋落方式死亡,药物主要作用于间期细胞,其杀伤机构的始动环节可能与核酸代谢障碍无关。
This article studied the effects of triptolide on DNA and RNA sysntheses of FGC_(85) cells by means of scintillation counting as well as their ultrastructural changes with electron microscopy. The experimcnts indicated that after 12 h of treatment with triptolide(0.51μg/ml),both FGC_(85) cells and their mitotic figures were markediy decreased.Under light microscope the majority of cells contracted and rounded,and died at last.Electron microscopic studies have showed that the last ultrastructural changes of FGC_(85) were identical with those of“apoptosis”discribed by Kerr et al. Because the mitotic cells didn t show any abnormal change,it seems that triptolide only acts on the interphase cells. Since the drugs,which can induce apoptosis,are different in mechanism,we paid more attention on the early ultrastructural changes induced by triptolide,and its effects on DNA and RNA precursor incorporation of FGC_(85) cells.After 2 h of treatment with triptolide,nucleolar changes of FGC_(85) cells took place.After 4～8 h,nucleolar alterations got drastic.They consisted of nucleolar degranulation, appearence of perichromatin granules and nucleolar fragmentation.Surprisingly,at the same time triptolide had not any effect on the mitotic figures and 3~H-TdR,3~H-UR incorporation of FGC_(85) cell. While under the same experimental condition cytosine arabinoside and aetinomycin D inhibited the incorporation of 3~H-TdR and 3~H-UR into FGC_(85) cells respectively. Therefore the prmary target of action of triptolide on FGC_(85) cells does not lie in the disturbance of nuclcic acid synthesis.Effects of triptolide on cellular membrane and protein synthesis of FGC_(85) cell remain to be studied.
关键词
雷公藤
雷公藤内酯
胃癌
杀伤作用
triptolid
human stomach cancer cell line
radioautography
electron microscopy
