板蓝根抗内毒素活性部位的研究

 目的评价和比较板蓝根5个不同化学部位的抗内毒素作用。方法动态浊度法测定细菌内毒素浓度,观察板蓝根不同化学部位对D-氨基半乳糖敏化小鼠内毒素致死攻击的保护作用。并以内毒素制备家兔发热模型,测定其肛温变化。结果板蓝根Ⅳ部位体外对于内毒素的降解率达70%,体内降低动物死亡率至33%,发热抑制百分率为32.3%,表明其可以直接中和降解内毒素,显著降低内毒素的致热性和致死性。结论板蓝根Ⅳ部位具有显著的体内外抗内毒素活性。

Study on chemical fraction with anti-endotoxin activity from Radix Isatidis

OBJECTIVE To evaluate and compare the antiendotoxin activity of five different chemical fractions isolated from Radix Isa-tidis. METHODS By means of kinetic turbidimetric assay, the bacterial endotoxin content in the testing samples was determined. The protection for the mice sensitized by D-galactosamine from endotoxin-induced lethality was investigated.The changes of rectal temperature were observed in feverous rabbits induced by endotoxin. RESULTS Upon the neutral effect of fraction Ⅳ from Radix Isatidis, endotoxin was degraded by 70 % in vivo. Meanwhile, the rates of pyrogenicity and lethality induced by endotoxin respectively were decreased to 32.3 % and 33 % . CONCLUSION Fraction Ⅳ can neutralise endotoxin directly, and inhibit pyrogenicity and lethality induced by endotoxin.Fraction Ⅳ from Radix Isatidis is shown to have remarkable anti-endotoxin activity in vitro and in vivo.