Effect of anthracycline drugs on the element content of cultured embryonic rat cardiomyocytes.

The effect of two anthracyclines--doxorubicin hydrochloride (adriamycin, CAS-25316-40-9), and 4'-epidoxorubicin (epirubicin, CAS-56420-45-2), and an anthracenedione, mitoxantrone (CAS-70476-82-3) on the element content of cultured embryonic rat cardiomyocytes was examined by X-ray microanalysis. Adriamycin induced an increase in Ca, P and S, and a decrease in Cl content. Novantrone caused a marked increase in the Na and a decrease in the Cl content, whereas epirubicin did not affect the content of any of the elements examined. In an attempt to prevent the effect of the drugs on the element content of the cells, the cardiomyocytes were incubated with a blocker of the slow Ca channels--verapamil-- and with each of the three drugs. Verapamil only induced an increase in the Ca and a decrease in the S content of the cells. Except for some protective effect on the element content of the cardiomyocytes, which was altered by adriamycin, the results did not indicate any beneficial effect of verapamil added to the other two drugs, as for this aspect of the study.