Accumulation and efflux of doxorubicin in mitochondria isolated from HEK cells and ST-HEK cells.

<p>Mitochondrial fractions were isolated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050082#s2" target="_blank">Materials and Methods</a>. Mitochondrial preparations of HEK cells (A) and ST-HEK cells (B) were incubated with 5 µM doxorubicin for 10 min, then mitochondria were washed with doxorubicin-free buffer A with or without 1 µM Ko143 and incubated for 1 h. <i>Left panel</i>, contents of doxorubicin in mitochondria were analyzed using a flow cytometer. A representative histogram of three independent experiments is shown. <i>Right panel</i>, bar graphs show the flow cytometric analysis of the mitochondrial doxorubicin contents. Results represent the mean ± SD of three independent experiments. Black bar indicates autofluorescence (Auto); red bar, doxorubicin treatment (DXR); yellow bar, wash without Ko143 (Wash); green bar, wash with Ko143 (Wash+Ko143). **<i>P</i><0.01 vs. DXR. †<i>P</i><0.01 vs. Wash.