板蓝根不同极性部位对内毒素致小鼠死亡率的影响

为比较板蓝根氯仿提取物（Ⅰ）及其四个不同极性组份（Ⅱ，Ⅲ，Ⅳ，Ⅴ）对内毒素致小鼠死亡率的影响。以尾静脉注射卡介苗（BCG）增敏，将增敏后小鼠分别用100g/L样品液0.4ml灌胃。1.5h后尾静脉注射内毒素（2.42mg/kg），同时设内毒素对照组和空白对照组，观察其死亡结果。内毒素对照组小鼠死亡率为70%，Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组小鼠死亡率分别为30%、50%、20%、50%、60%，其中，Ⅰ、Ⅲ组结果与内毒素组比有显著差异（P<0.05）。认为第Ⅲ组能明显拮抗内毒素毒性，延长小鼠生存时间，提高小鼠存活率，与其他组份相比，效果最佳，第Ⅲ组为板蓝根抗内毒素活性物质组。

The Protective Effects of Different Polar Fractions from Radix Isatids on Endotoxin Challenged Mice

To compare the protective effects of chlorform extact (I) and its four polar fractions (Ⅱ，Ⅲ，Ⅳ，Ⅴ) from Radix Isatids on endotoxin (LPS) challenged mice，the mice were primed with BCG by injection via tail vein and were given 100 g/L drugs solution by PO after 10 days. 1.5 h later，2.42 mg/kg LPS was given to the mice through a tail vein. At the same time，the endotoxin challenged control group and blank control group were established. The mortality and the protective effects were observed. The mortality of the mice in the endotoxin challenged control group was 70 %，while the mortality of the mice in the Ⅰ,Ⅱ，Ⅲ，Ⅳ and Ⅴ groups was 30 %，50 %，20 %，50 % and 60 % respectively，with the difference being significant between groups Ⅰ or Ⅲ and endotoxin challenged group (P<0.05). It was concluded that Ⅲ could protect BCG-primed mice from LPS-induced lethality and antagonize the action of LPS in vitro in mice. Ⅲ was the anti-endotoxin active material in Radix Isatids.