Cardiac function and structure were measured with echocardiography.

<p>(A). Ejection fraction (B), fraction shortening (C), stroke volume (D), left ventricular internal diastolic diameter (E), left ventricular posterior wall (LVPW) end diastolic thickness (F), and left ventricular end diastolic volume (G) were calculated with the formula stored in the echo machine by the manufacturer. The data are presented as the mean ± SEM (n = 5–7 in each group). Scale for time = 0.2 sec; scale for length = 1cm. ^†<i>P</i> < 0.05, ^‡<i>P</i> < 0.01 compared with the control group (Con); *<i>P</i> < 0.05, **<i>P</i> < 0.01 compared with the Dox group (one-way ANOVA).