A recent study has shown that
amiodarone inhibits the production of
cytokines in vitro. This study was performed to examine the effects of
amiodarone on survival, heart weight-to-
body-weight ratio (HW/BW), myocardial lesions and
cytokines production in a murine model of viral
myocarditis induced by the encephalomyocarditis virus (EMCV). Four-week-old male DBA/2 mice were inoculated with the EMCV. To examine its effect on survival and HW/BW on day 14, mice were administered oral
amiodarone (30 mg/kg) or the vehicle only once daily, starting 4 days before inoculation of the virus. The effects of
amiodarone on histopathologic changes in myocardial lesions and myocardial
cytokine production were studied in mice treated with
amiodarone (10 mg/kg or 30 mg/kg) or vehicle, and killed day 7. The survival rate on day 14 was significantly higher in the
amiodarone-treated mice than in the control mice. The HW/BW, histopathologic score of cellular infiltration and myocardial
interleukin 6 concentration were significantly lower in the
amiodarone-treated group than in the control group. Likewise, myocardial necrotic area was significantly smaller in the
amiodarone group than in the control group. This study suggests that the beneficial effects of
amiodarone in viral
myocarditis may be mediated by decreasing
interleukin 6 production in myocardial tissue.