Intracellular changes of HeLa cells after single or repeated treatment with cytostatics

HeLa cells were treated once or repeatedly using the cytostatics doxorubicin (adriamycin, Ad, CAS 23214-92-8), cisplatin (Pt, CAS 15663-27-1) and fluorouracil (FU, CAS 51-21-8). Intracellular GSH (reduced glutathione) contents, activities of protein kinase C, cytotoxicity and membrane fluidity were investigated. During single treatment protein kinase C activities as well as membrane fluidity increased, whereas intracellular GSH decreased. With repeated treatments protein kinase C activities increased further. Membrane fluidity as well as intracellular GSH contents increased. The investigated parameters may be correlated with sensitivity of cells against cytostatics.