Interaction of rhodamine 123 with mitochondria isolated from drug-sensitive and -resistant Friend leukemia cells.
Mitochondria isolated from Friend leukemia cell lines sensitive (FS) and resistant (FR) to rhodamine 123 (Rho123), showed respiratory control and ADP/O ratios indicative of well-coupled oxidative phosphorylation activity. When Rho123 was added to mitochondria from both cell lines, respiratory State 4 increased. The increase was higher in mitochondria isolated from resistant than from sensitive cells. Respiratory State 3 was slightly more inhibited by Rho123 in resistant than in sensitive cell mitochondria (98 and 82% inhibition, respectively). While it is not clear how the uncoupling-like effects of Rho123 on State 4 contribute to cellular toxicity, our results indicate that differential cellular sensitivity to the drug does not correlate with inhibition of oxidative phosphorylation in mitochondria isolated from drug-sensitive and -resistant cells.
D000818:Animals; D002460:Cell Line; D004396:Coloring Agents; D004351:Drug Resistance; D005622:Friend murine leukemia virus; D007942:Leukemia, Experimental / Q000378:metabolism*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects; D020112:Rhodamine 123; D012235:Rhodamines / Q000494:pharmacology*; D014966:Xanthenes / Q000494:pharmacology*
D004396:Coloring Agents; D012235:Rhodamines; D014966:Xanthenes; D020112:Rhodamine 123; C044776:rhodamine 116