【摘要】 目的研究板蓝根中4(3H)-喹唑酮(QZO)的抗内毒素作用。方法鲎试验法测定抗内毒素;内毒素致家兔发热实验检测其体内抗内毒素作用;脂多糖致小鼠死亡实验测定QZO的保护作用及其对脂多糖致小鼠过度释放肿瘤坏死因子(TNFα)和一氧化氮(NO)的影响,研究QZO的抗内毒素作用。结果0.832 mg.ml-1QZO可使4 EU内毒素降解为1.19 EU,破坏率71.31%;0.5%QZO溶液可使内毒素引起的家兔体温升高显著降低,使同剂量脂多糖引起的小鼠死亡率从70%降为30%;板蓝根中的QZO可抑制脂多糖致小鼠血清中TNFα和NO的过度释放,抑制率呈剂量依赖性。结论从板蓝根中提取分离出的QZO有抗内毒素作用。更多还原

【Abstract】 OBJECTIVE To study the anti-endotoxic effect of 4(3H)-quinazolinone(QZO) isolated from Radix Isatidis.METHODS QZO was extracted and isolated from Radix Isatidis and diluted into 0.5% solution.The content of endotoxin pretreated with QZO was quantitatively determined using Limulus test.The inhibition of endotoxin-induced fever by QZO was measured in rabbits.The Lipopolysaccharide(LPS)-induced death in mice pretreated with and without QZO was compared.Influence on the LPS-induced release of TNFα and NO in macrophages from mice was studied.RESULTS After pretreatment with QZO,71.31% of endotoxin was destroyed,the endotoxin-induced fever in rabbits decreased significantly;the rate of LPS-induced death in mice dropped from 70% to 30%.The excessive release of TNFα and NO induced by LPS in mice could be inhibited by QZO from Radix Isatidis and the percentage of inhibition was dependent on the dosage.CONCLUSION QZO isolated from Radix Isatidis possesses anti-endotoxic effects.更多还原