Verapamil effect on the accumulation of doxorubicin in the leukemia P388 cells with induced antibiotic resistance.

Using mice BDF1 it has been shown that the period of retention of Doxorubicin (Dx) is shorter in the leukemia P388 cells with induced antibiotic resistance (P388/Dx) as compared to P388 cells sensitive to Dx. Administration of Verapamil (Vp) to animals leads to an increase of Dx concentration in the leukemia P388/Dx cells during a 240 min observation period. Vp promotes the therapeutic effect of Dx on P388/Dx bearing mice. It can be suggested that the mechanism of Vp action consists in the damaged Dx elimination from cells with induced resistance, since Vp doesn't change the period of circulation of the antibiotic in the blood plasma of mice.