The effect of doxorubicin (adriamycin) on cytoplasmic microtubule system in cardiac cells.

The objective of this study was to determine whether the antineoplastic agent doxorubicin (adriamycin) affects the microtubule system in isolated cardiac cells. Embryonic chick heart cultures were exposed to adriamycin concentrations of 40, 80, or 200 microM for 3, 12, or 24 h before fixation prior to immunofluorescence. Adriamycin produced marked distortions in the normal microtubule system. This was a function of adriamycin concentration and the duration of the exposure to adriamycin. Even when adriamycin was removed from the medium for a 12 h period, cells treated with adriamycin showed abnormalities of the microtubule system. The effect of adriamycin on the microtubule system extends to its reassembly after colchicine. Cells allowed to recover after colchicine in the presence of adriamycin (40 microM) showed impairment in microtubule regeneration. These data indicate that the microtubule system in cardiac myocytes is affected by adriamycin both by damaging microtubule structure and by impairing microtubule reassembly.