The Antipyretic And Anti-inflammatory Effects Of Qingkailing Freeze-dried Powder For Injection And Its Antipyretic Mechanism

Objective By the rabbit model of 2,4-dinitrophenol-induced fever and the rat model of endotoxin-induced fever, to investigate the antipyretic effects of different doses of Qingkailing Freeze-dried Powder for Injection (QI). By the rat model of hind paw edema induced by carrageenan, to investigate the anti-inflammatory effects of different doses of Qingkailing Freeze-dried Powder for Injection(QI). In the endotoxin-induced fever, radioimmunoassay was adopted to detect the levels of IL-1βand cAMP in the hypothalamus of rats. The aim is to evaluate the antipyretic effects and anti-inflammatory 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 was adopted to prepare model of fever caused by 2,4-dinitrophenol. Pure breed of rabbits were grouped into five random groups, i.e. analgin group(positive control),NS group(negative control),Qingkailing Freeze-dried Powder groups(74.50mg/kg, 37.25mg/kg, 18.625mg/kg). Basal body temperature was measured and intravenous injection of drugs was administered, and 10 minutes later, subcutaneous injection of 2,4-dinitrophenol(1.50mg/kg)was administered to prepare model of fever caused by 2,4-dinitrophenol.30minutes,1,2,3,4 and 6 hours later, the changes of body temperature were measured and the differences between body temperature and basal body temperature were taken as the result. The rat model of endotoxin-induced fever was established to prepare model of fever caused by endotoxin. Rats were grouped into four random groups, i.e. analgin group(positive control),NS group(negative control),Qingkailing Freeze-dried Powder groups(298.00mg/ kg, 149.00mg/kg). Basal body temperature was measured and intravenous injection of drugs was administered, and 10 minutes later, intraperitoneal injection of endotoxin(50μg/kg) was administered to prepare model of fever caused by endotoxin. 20,40 minutes and 1 hours later, the changes of body temperature were measured and the differences between body temperature and basal body temperature were taken as the result. Then, rats were killed and the hypothalamuses were taken out of. Radioimmunoassay was adopted to detect the levels of IL-1βand cAMP in the hypothalamus of rats. The anti-inflammatory effects were observed in rats with hind paw edema induced by carrageenan. Male rats were grouped into five random groups, i.e. hexadecadrol group(positive control),NS group(negative control),Qingkailing Freeze-dried Powder groups(298.00mg/kg, 149.00mg/kg, 74.50mg/kg). Intravenous injection of drugs was administered, and hypodermic injection of carrageenan was administered to prepare model of hind paw edema induced by carrageenan. 30minutes,1,2,3,4 and 5 hours later, the thicknesses were measured and the increases of thickness after inflammation were taken as the result.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-1βand cAMP in the hypothalamus. QI also remarkably lessen the degree of carrageenan-induced paw edema.Conclusions QI has antipyretic and anti-inflammatory effects. Its mechanism of the antipyretic effect on rats may be the inhibiting of the production of IL-1βand accordingly decreasing cAMP in the hypothalamus.