C57BL/6 Mice are More Appropriate than BALB/C Mice in Inducing Dilated Cardiomyopathy with Short-Term Doxorubicin Treatment

Objective: To develop an appropriate method to induce the model of dilated cardiomyopathy in mice with doxorubicin.Methods and Results: Twenty C57BL/6 mice and twenty BALB/C mice were divided into four groups. group A: C57BL/6 (n=10), administered doxorubicin 2.0 mg/kg, every other day for 8 days, then once a week for 6 weeks, for a total cumulative dose of 20 rug/kg: group B: C57BL/6 (n=10), administered doxorubicin 2.5 rug/kg, every other day for 12 days for a total cumulative dose of 15 rug/kg: group C: BALB/C (n=10), administered doxorubicin 2.5 rug/kg, every other day for 12 days for a total cumulative dose of 15 mg/kg: group D: BALB/C (n=10), administered doxorubicin 2.0 rug/kg, every other day for 8 days, then once a week for 6 weeks, for a total cumulative dose of 20 mg/kg. Echocardiography was done before and after the study. There is no significant difference in survival between group B and group C (90% vs 90%). However, survival was significantly lower in group D compared with group A (30% vs 90%, p＜0.05). The ejection fraction was markedly decreased and the left ventricular end-diastole diameter was markedly increase d in groups A. B and D after DOX injection, but not in group C.Conclusion : C57BL/6 mice arc more suitable than BALB/C mice for inducing dilated cardiomyopathy with short-term doxorubicin treatment. Intraperitoneal injection of doxorubicin in C57BL/6 mice (2.5 mg/kg, every other day for 12 days. for a total cumulative dose of 15 mg/kg) is a reliable method to induce dilated cardiomyopathy.