AIM : To investigate the antipyretic mechanisms of the
chuanhuning injection in rats. METHODS : The fever model was made
by suspension of yeast which was injected hypodermically to the rats. The contents of PGE 2 and cAMP in
hypothalamus were measured by radioisotope method. RESULTS : The maximal increment in body temperature (ΔT) and 6 h thermal response index(TRI 6) in the model group were significantly higher than those in the control group ( P < 0.01 ), ΔT in chuanhuning 125 mg·kg -1 group and 250 mg·kg -1 group and TRI 6 in chuanhuning 250 mg·kg -1 group were lower than those in the model group( P BZ < 0.01 ), and ΔT and TRI 6 in chuanhuning 250 mg·kg -1 group were lower than those in chuanhuning 125 mg·kg -1 group ( P BZ < 0.01 ). The contents of PGE 2 and cAMP in hypothalamus in model group were more higher than those in the control group ( P < 0.01 ), the contents of PGE 2 and cAMP in the chuanhuning groups were lower than those in the model group ( P < 0.01 ), and the contents of PGE 2 and cAMP in chuanhuning 250 mg·kg -1 group were lower than those in chuanhuning 125 mg·kg -1 group ( P < 0.05 ). ΔT is positively correlative with the contents of PGE 2 and cAMP in hypothalamus ( P BZ < 0.01 ). CONCLUSION : The antipyretic mechanisms of
chuanhuning injection may be related to its decreasing the contents of PGE 2 and cAMP in hypothalamus, and the effects are dosage dependence.