Modulation　of　multidrug　resistance　by　three　bisbenzyl-isoquinolines　in　comparison　with　verapamil

比较轮环藤碱（Ｃｙｃ）、海岛轮环藤碱（Ｉｎｓｒ）和海岛轮环藤酚碱（Ｉｎｓｎ）与维拉帕米（Ｖｅｒ）体外调节多药耐药性（ＭＤＲ）的作用．方法：细胞毒试验采用ＭＴＴ法，细胞内阿霉素（Ｄｏｘ）积累采用荧光分光光度法测定．结果：Ｃｙｃ，Ｉｎｓｒ，Ｉｎｓｎ和Ｖｅｒ在ＭＤＲ细胞系ＭＣＦ７／Ａｄｒ和ＫＢｖ２００能显著调节Ｄｏｘ和长春新碱的耐药性，且其作用呈剂量依赖性．Ｃｙｃ，Ｉｎｓｒ，Ｉｎｓｎ和Ｖｅｒ均能增加ＭＣＦ７／Ａｄｒ细胞内Ｄｏｘ的积累．Ｃｙｃ和Ｉｎｓｒ调节ＭＤＲ作用明显优于Ｖｅｒ，而Ｉｎｓｎ的作用类似于Ｖｅｒ．结论：Ｃｙｃ，Ｉｎｓｒ和Ｉｎｓｎ能通过增加ＭＤＲ细胞内Ｄｏｘ的积累而调节ＭＤＲ．

AIM: To compare cycleanine (Cyc), insularine (Insr), insulanoline (Insn) and verapamil (Ver) in modulation of multidrug resistance (MDR) in vitro . METHODS: The cytotoxic effect was determined by 3 [4,5 dimethylthiazol 2 yl], 5 diphenyl tetarzolium bromide (MTT) assay. The intracellular doxorubincin (Dox) accumulation was assayed by spectro fluorometer. RESULTS: Cyc, Insr, Insn, and Ver showed significant activities in modulating Dox and vincristine resistances in acquired resistant MCF 7/Adr and KB v200 cell lines in a dose dependent manner. Cyc, Insr, Insn, and Ver increased intracellular Dox accumulation in MCF 7/Adr cells. Cyc and Insr had greater activities than Ver in modulating MDR, while Insn had similar activity to that of Ver. CONCLUSION: MDR was modulated by Cyc, Insr, and Insn, due to the increase of intracellular Dox accumulation.