羊瘙痒因子263K经颅内注射感染仓鼠后半数致死量(LD_(50))的测定  

Measurement of LD_(50) of scrapie agent strain 263K in hamsters through intracerebral route

作　　者：石琦[1] 张宝云[1] 高晨[1] 韩俊[1] 高永军[1] 周玉玲[2] 董小平[1] 

机构地区：[1]传染病预防控制国家重点实验室,中国疾病预防控制中心病毒病预防控制所,北京100052 [2]西安交通大学医学院

出　　处：《中国人兽共患病学报》2006年第3期252-255,共4页Chinese Journal of Zoonoses

基　　金：国家自然科学基金委项目(30070038);国家自然科学基金委重点项目(30130070);国家863计划项目(2001AA215391);欧盟项目(QLRT200001441);国家科技攻关计划项目(2003BA712A04-02)资助。

摘　　要：目的测定羊瘙痒因子263K经颅内注射感染仓鼠后的LD50。方法将感染羊瘙痒因子263K的仓鼠脑组织用生理盐水制成10%(w/v)脑组织匀浆,梯度稀释后感染仓鼠,观察仓鼠的发病情况。以Reed-Muench公式计算LD50,用West-ern blot方法检测观察期结束后发病及仍存活的仓鼠脑组织、脾组织中抵抗蛋白酶K的PrPSc。结果当颅内接种稀释度由低到高变化时,仓鼠发病的潜伏期及病程同时也由短到长发生变化。发病仓鼠脑组织中可以检测到PrPSc,但是PrPSc的量在不同的组之间无太大差别。观察期结束后,仍存活的仓鼠脑组织中未检测到具有PK抗性的PrP信号。结论本实验室保存的羊瘙痒因子263K经颅内注射感染仓鼠的LD50为9.2-log10LD50i.c.units/0.001g brain,即当对仓鼠颅内接种10μl羊瘙痒因子263K的10-9.2稀释液时,50%的仓鼠会死亡。To determine LD50 of scrapie agent strain 263K in hamsters through intracerebral route, hamsters were infected intracerebrally with 10-fold diluted 10 % homogenates of the infected hamster brain tissues from dilution of homogenates from 10-1 to 10-10 and the LDs0 value was calculated with Reed-Muench＇s method. The presence of PrP^Sc in the brain and spleen tissues of the clinical onset or the living hamsters to resist the action of proteinase K was screened by Western blot analysis. It was found that incubat.ion periods and clinical courses of disease varied greatly with the amounts of infectious agent inoculated, showing a remarkable dose - dependent manner. PrP^Sc could be detected in the brain tissues of the diseased hamsters, but the amount of PrP^Sc in brains was comparable among different groups, indicating that it was not related to the initiative concentration of the infectious agent. Proteinase K- resistant PrP signal was not observed in the brain tissues of the survival animals receiving 10- 9 and 10-10 dilutions of agent at the end of observation. It is concluded the LD50 of scrapic agent 263K kept in our laboratory is 9.2-1og10, that is, the intracerebral inoculation of 10μl of scrapic agent 263K at dilution of 10-9.2 causes 50% of death in the infected hamsters.

关 键 词：羊瘙痒因子263K 半数致死量 颅内注射 

分 类 号：R373.9[医药卫生—病原生物学]