杀菌性/通透性增加蛋白模拟肽小鼠体内拮抗内毒素作用的研究

Studies on the anti endotoxin activity of modeling peptides of bactericidal/permeability increasing protein in vivo

目的：观察杀菌性／通透性增加蛋白（ＢＰＩ）模拟肽对内毒素（ＬＰＳ）攻击所致小鼠死亡的保护作用。方法：以一个ＬＤ５０的ＬＰＳ（２０ｍｇ·ｋｇ－１）静脉注射攻击小鼠，分别于ＬＰＳ攻击后２０ｓ内静脉注射不同剂量的ＢＰＩ模拟肽；于ＬＰＳ攻击前及攻击后不同时间内分别静脉注射５ｍｇ·ｋｇ－１和１０ｍｇ·ｋｇ－１的ＢＰＩ模拟肽，以观察ＢＰＩ模拟肽对ＬＰＳ攻击所致小鼠死亡的保护作用、ＢＰＩ模拟肽对ＬＰＳ攻击小鼠死亡保护作用的时效关系及ＢＰＩ模拟肽对ＬＰＳ攻击小鼠死亡的预防作用。结果：ＢＰＩ模拟肽对ＬＰＳ所致小鼠死亡有明显的保护作用及预防作用，并有一定的量效关系及时效关系。结论：ＢＰＩ模拟肽，不仅保留了ＢＰＩ特异性中和ＬＰＳ的特性。

Objective: To observe the protective effects of BPI modeling peptides on LPS challenged mice. Methods: One LD 50 dose of LPS was injected to challenge mice, and different dose of BPI modeling peptides was injected within 20 s after the challenging and then 5 mg·kg -1 /10 mg·kg -1 dose of BPI modeling peptides was injected pre/post the challenging respectively, to observe the protective or preventive effects of BPI modeling peptides on the LPS challenged mice. Results: It was found that BPI modeling peptides had a significant protective effect on endotoxin (20 mg/kg) challenged mice and when the peptides administered with LPS at the same time or after that of LPS within 10 s, it had a significant protective effects, and when administered 30 min after that of LPS, it had no significant protective effect; when administered 60 min to 10 s before LPS challenging, it still had a significant protective effect. Conclusion: BPI modeling peptides seems had a much longer half life time and the protective effect on LPS challenged mice could be better than that of BPI.