Effects of recombinant human alpha-interferon in a rodent cardiotoxicity model

Recombinant human alpha-interferon infused intravenously into rats at doses of 10(6) (1st infusion) and 10(5) IU (2nd and 3rd infusion) produced marginal evidence of liver damage but no serious toxicity. During the 2nd and 3rd infusions an increased incidence of cardiac arrhythmias of various types was observed. In 2 rats electrocardiographic evidence of myocardial ischemia was noted. No changes in myocardial structure were demonstrated by light and electron microscopy. With the high dose the decrease in body temperature resulting from anesthesia was significantly reduced. Antibodies to interferon were demonstrated in the majority of the animals.