[Pharmacokinetic study of aclarubicin. The distribution of the preparation and its biologically active metabolites in rat tissues].

Tissue pharmacokinetics of aclarubicin and its active metabolites was studied with high performance liquid chromatography. The drug was administered to rats intravenously in single doses of 5 and 10 mg/kg and orally in a single dose of 10 mg/kg. With both the administration routes the highest concentrations of the drug and its metabolites were attained in the lymph nodes. Then followed the spleen and lungs. The lowest content of the drug was detected in the heart. The total values of the areas under the concentration/time curves for aclarubicin and its metabolites in the tissues of the heart, lungs, lymph nodes and spleen after oral administration were respectively 2, 3, 4 and 7 times lower than those after the drug intravenous administration in the same dose. The concentrations of the active metabolites MA144N1 and MA144T1 exceeded those of aclarubicin and were detected in the tissues within a longer period as compared to the unchanged drug. With repeated administration preferential accumulation of the metabolites in the tissues and their increased contribution to the aclarubicin antitumor effect could be suspected.