Medoff J, Medoff G, Goldstein M N, Schlessinger D, Kobayaski G S
Cancer Res. 1975 Sep;35(9):2548-52.
HeLa cells, which were selected for resistance to actinomycin D on the basis of decreaded penetration of the antibiotic into the cells, were treated with nontoxic concentrations of the polyene antibiotic amphotericin B. In the presence of amphotericin B, the cells became sensitive to the effects of actinomycin D, as demonstrated by loss of cell viability, typical morphological changes, and effects on the pattern of RNA synthesis. Furthermore, we were able to demonstrate that amphotericin B increased the amount of (3H)actinomycin D incorporated into HeLa cells as determined by both radioactive counts and radioautography. Amphotericin B might be useful in overcoming the resistance is based on decreased entry of the agents into cells.
HeLa细胞是基于抗生素进入细胞的渗透率降低而被选出来对放线菌素D具有抗性的，用无毒浓度的多烯抗生素两性霉素B对其进行处理。在两性霉素B存在的情况下，细胞对放线菌素D的作用变得敏感，这通过细胞活力丧失、典型的形态学变化以及对RNA合成模式的影响得以证明。此外，我们能够证明，通过放射性计数和放射自显影测定，两性霉素B增加了掺入HeLa细胞中的（3H）放线菌素D的量。两性霉素B可能有助于克服基于药物进入细胞减少而产生的抗性。
