Sugimoto Y, Nishimura T, Suzuki H, Tanaka N
J Antibiot (Tokyo). 1981 Sep;34(9):1200-5. doi: 10.7164/antibiotics.34.1200.
Activities of marker enzymes for various cell components were studied with extracts of adriamycin-, aclacinomycin A- and bleomycin-resistant cells and with partially purified plasma membrane fraction of aclacinomycin A-resistant cells, in comparison with those of the parental cells. Alkaline phosphodiesterase and Na+-K+-ATPase activities were observed to alter in the drug-resistant sublines, but other enzymes showed similar activities in the resistant cells to those in the parental cells. Alkaline phosphodiesterase activities in all the resistant sublines were higher than that in the parental cells. Na+K+-ATPase activities of anthracycline-resistant sublines were lower and that in bleomycin-resistant cell line was higher than that of the parental cells. The adriamycin-resistant cells exhibited the same level of alkaline phosphodiesterase activity with the aclacinomycin A-resistant cells: Vmax was the same with, and the affinity was twice stronger than the parental cells. The bleomycin-resistant cells showed ca. 30% Vmax in comparison with the sensitive cells, and 17 fold higher affinity than the parental cells. The current results, concerning changes of membrane-associated enzymes in drug-resistant sublines of L5178Y cells, support the assumption that the resistance is due to alteration of plasma membrane transport systems.
用阿霉素、阿克拉霉素A和博来霉素抗性细胞的提取物以及阿克拉霉素A抗性细胞的部分纯化质膜组分，研究了各种细胞成分的标记酶活性，并与亲代细胞进行了比较。观察到碱性磷酸二酯酶和Na⁺-K⁺-ATP酶活性在耐药亚系中发生改变，但其他酶在耐药细胞中的活性与亲代细胞相似。所有耐药亚系中的碱性磷酸二酯酶活性均高于亲代细胞。蒽环类抗生素耐药亚系的Na⁺K⁺-ATP酶活性较低，而博来霉素耐药细胞系中的该酶活性高于亲代细胞。阿霉素抗性细胞与阿克拉霉素A抗性细胞表现出相同水平的碱性磷酸二酯酶活性：Vmax相同，亲和力是亲代细胞的两倍。与敏感细胞相比，博来霉素抗性细胞的Vmax约为30%，亲和力比亲代细胞高17倍。目前关于L5178Y细胞耐药亚系中膜相关酶变化的结果支持了耐药性是由于质膜转运系统改变的假设。
