[Study on the antipyretic, analgesic effects of qingkailing freeze-dried powder for injection and its antipyretic mechanism].
OBJECTIVE: To investigate the antipyretic, analgesic effects of Qingkailing Freeze-Dried Powder for Injection (QI) and its mechanism of the antipyretic effect. METHODS: The rabbit model of 2, 4-dinitrophenol-induced fever and the rat model of endotoxin-induced fever were established and the body temperatures were observed. Radioimmunoassay was adopted to detect the levels of IL-1beta and cAMP in the hypothalamus of rats. The analgesic effects were tested by hot-plate and writhing reaction method. RESULTS: QI showed marked antipyretic effects on the 2,4-dinitrophenol-induced fever and the endotoxin-induced fever. At the same time, QI remarkably decreased the contents of IL-beta and cAMP in the hypothalamus. QI also remarkably reduced the frequency of acetic acid-induced writhing and delaied the time of licking rear feet. CONCLUSION: QI has antipyretic, analgesic effects. Its mechanism of the antipyretic effects on rats may be inhibiting the production of IL-1beta and accordingly decreasing cAMP in the hypothalamus.