Objective: To investigate the effect of forsythiaside A(FA) on body temperature

heat-regulating center and temperature-sensitive transient receptor potential(TRP) A1 expression of mice with yeast induced fever

so as to elucidate the mechanism of the antipyretic effect and potential mechanism of FA. Method: Sixty male C57BL/6 mice were randomly divided into six groups:normal group

model group

different dosages(2

4

8 mg·kg-1) of FA-treated group

aspirin group(as the positive control

90 mg·kg-1)

with 10 mice in each group. The pyrexia model was induced by injection of yeast suspension subcutaneously. Rectal temperature was recorded before and 17-22 h after pyrexia induction. At the 22 h after injection of yeast

the mice were sacrificed to collect their hypothalamus and dorsal root ganglion(DRG). The expression of TRPA1 was detected by immunohistochemistry and Western blot. Result: Compared with the normal group

the rectal temperature of the mice in the model group notably increased after injection of yeast

reaching the peak at 17 h(P<0.01). In the meanwhile

the TRPA1 level in hypothalamus and DRG of the model group significantly reduced. Compared with the model group

FA(4

8 mg·kg-1) group showed significant decrease in the elevated temperature of mice induced by yeast

and up-regulation in the expression of TRPA1 in paraventricular nuclei(PVN)

supraoptic nucleus(SO) and DRG(P<0.05

P<0.01). Conclusion: FA can reduce the temperature of fevered mice induced by yeast

which may be related to their effective regulation of TRPA1 in hypothalamus and DRG.