Abstract: AIM: To study the effects of body temperature changes inmice induced by intravenously and intramuscularly injection of different dosage of rhIFNα2a. METHODS: The body temperature in mice was measured at 30 minute before and at different time after rhIFNα2a injection and the concentration of IFN in serum was measured by ELISA method.RESULTS: Intravenous injection of rhIFNα2a induced remarkably higher and longer fever than intramuscular injection.And the fever increase was inhibited by indomethacin.CONCLUSION: Intramuscular injection of rhIFNα2a shows fewer side effects than intravenous injection.Fever change sensitive to rhIFNα2a can be inhibited by using non-steroid anti-inflammatory drugs.

Key words: rhIFNα2a, endogenous pyrogen, fever, mice, temperature