Abstract: AIM: To explore the antipyretic mechanisms of Yuxingcao injection in rats. METHODS: The fever model was made by suspension of yeast which was injected hypodemically to the rats.The contents of cAMP in hypothalamus and AVP in ventral septal area(VSA) were measured by radioisotope method. RESULTS: Yuxingcao injection possessed obvious antipyretic effect on fever rats and inhibited the increase of cAMP in hypothalamus and promoted the release of AVP in VSA.Correlation analysis showed that contents of cAMP in hypothalamus and AVP in VSA were positively correlated with the change of body temperature of rats. CONCLUSION: The antipyretic mechanisms of Yuxingcao injection may be due to inhibiting the increase in cAMP in hypothalamus and promoting the release of AVP in VSA, and the effects are dosage-dependence.

Key words: Yuxingcao injection, fever, cAMP, arginine vasopressin