OBJECTIVETo study the antipyretic effect of baicalin in inhibiting yeast-induced fever in rats and the influence on inflammatory cytokine, then explore the possible mechanism of baicalin in inhibiting yeast-induced fever in rats.

METHODSRat modles of pyrexia were established by subcutaneous injection of yeast (2 g x kg(-1)); the rats of were divided into the normal control, model, baicalin high, medium and low-dose group and the effect of baicalin on the changes of the rats' temperature were observed. Dual antibody ELISA method was used to test the changes of IL-6, IL-1beta and TNF-alpha contents in in serum , hypothalamus and cerebral spinal fluid (CSF). Then analyze the correlation between the inhibition ratio of temperature heighten on three different dose of baicalin and the inhibition ratio of the contents heighten on IL-6, IL-1beta and TNF-alpha.

RESULTThe high dose of baicalin significantly inhibited the yeast-induced fever of rats, and decresesed IL-6, IL-1beta and TNF-alpha contents in serum, hypothalamus and CSF. The inhibition ratio of temperature heighten of baicalin had direct correlation with the inhibition ratio of the heighten on IL-1beta content in serum, hypothalamus and CSF (r = 0.873, P < 0.05), also dose TNF-alpha (r = 0.862, P < 0.01).

CONCLUSIONBaicalin may have obvious antipyretic effect by decreasing the increasing contents of IL-1beta and TNF-alpha in rats.