低温保存内生致热原对其致热活性的影响

Effect of EP perserved at low temperature on pyrogenic activity

本实验用家兔全血加精制大肠杆菌内毒素，体外培养提取粗制家兔内生致热原（ｅｎｄｏｇｅｎ－ｏｕｓｐｙｒｏｇｅｎ，ＥＰ）。给大鼠静脉注射复制发热模型，观察了不同温度保存和不同时间保存的ＥＰ对其致热活性的影响。结果表明：４℃保存３天，４０℃保存３天、７天、３０天和１８０天的ＥＰ与４℃保存１天的ＥＰ比较，其发热第一时相发热峰值（△Ｔ）和１小时体温反应指数（ＴＲＩ）均无显著性差异（Ｐ＞０．０５）。发热第二时相△Ｔ和第二时相１小时ＴＲＩ，在４℃保存３天和－４０℃保存３天，７天的ＥＰ与４℃保存１天的ＥＰ比较无显著性差异（Ｐ＞０．０５）但－４０℃保存３０天和１８０天的ＥＰ，其第二时相△Ｔ和１小时ＴＲＩ明显下降（Ｐ＜０．０１）。４℃保存７天的ＥＰ，致热活性消失。提示，粗制ＥＰ的致热活性与保存温度和时间有一定关系。低温保存的ＥＰ可以明显的延缓ＥＰ致热活性的衰减。

he EP which was drawn out from the leukocyte of rabbit was injected intravenously to rat to induce fever.The effect of stored EP at low temperature and length Of stored time on their pyrogenic activity were observed. The result showed that the temperature response index(TRI)and fever peak(△T)in first peak of fever caused by EP which had been stored at 4℃ for 3 day;and-40℃ for 3 day,7 day,3 0 day and 18 0 day was not obviOusly decreased as compa red with the EP stored at 4℃for l day (P>0.05),The AT and TRI in second phase of fever of EP stored at 4℃ for 3 day and-40 ℃ for 3 day and 7 day showed not much difference(P>0.05).EP stored at -40℃ for 30 day and 180 day(P<0 .01)while compared with that stored at 4℃ for 7days,the pyrogenic activity of the latter was completely disappeared.The result indicatedthat the maintenance time of pyrogenic activity of EP at-40℃ is markedly longer thanthat at 4℃.