[The role of oxidative stress, caused by amiodarone, in the side effects of the drug].

It was supposed that free radicals are produced during the metabolism of amiodarone and involved in the mechanism of the drug's side effects. In vitro and in vivo experiments were performed in rats to check this hypothesis. We verified that amiodarone generated free radicals in vitro by chemiluminometric method. The light emission induced by amiodarone was inhibited by dihydroquinoline type antioxidants CH 402 and MTDQ--DA in a dose dependent manner. The malondialdehyde content, --one of the end products of lipid peroxidation--was increased by in vivo amiodarone administration in the serum and liver homogenate of rats. Amiodarone treatment increased significantly the NADPH and Fe3+ induced lipid peroxidation in rat liver microsomal fractions. The protective effect of antioxidants, MTDQ--DA and silibinin were ambiguous in these in vivo "short term" experiments.