羊瘙痒因子263K感染的金黄仓鼠脑中PrP^(Sc)的动态沉积特点  

Dynamic characteristics of PrP^(Sc) deposits in the hamsters' brain tissues inoculated intracerebrally with scrapie 263K strain

作　　者：韩俊[1] 高建梅[1] 李冰玲[2] 肖新莉[1] 高晨[1] 张宝云[1] 马贵平[2] 董小平[1] 

机构地区：[1]中国疾病预防控制中心病毒病预防控制所,北京100052 [2]北京出入境检验检疫局疯牛病检测实验室

出　　处：《中国人兽共患病杂志》2003年第2期26-30,共5页Chinese Journal of Zoonoses

基　　金：国家自然科学基金项目 ( 3992 80 18);( 30 0 70 0 38) ;国家自然科学基金重点项目 ( 30 130 0 70 ) ;国家 86 3计划项目 ( 2 0 0 1AA2 15391);欧盟项目 (QLRT2 0 0 0 0 14 41)资助

摘　　要：目的　观察羊瘙痒因子 2 63K感染的金黄仓鼠脑中PrPSc的沉积特点。方法　颅内接种羊瘙痒因子 2 63K感染金黄仓鼠 ,分别于接种后第 2 0天、40天、50天、60天和 70天取脑组织 ,用免疫组化法检测PrPSc的沉积 ,HE染色观察病理变化 ,Westernblot检测蛋白酶抗性PrPSc。结果　颅内接种 2 63K后第 2 0天 ,脑组织中即可检测到耐热和耐蛋白酶K的PrPSc的沉积 ,呈散在分布 ;第 40天可见细胞内PrPSc的沉积 ,第 50天脑组织中出现灶性、颗粒状、细胞内PrPSc的沉积 ,累及部位扩大 ,第60 - 70天可见弥漫性呈桑葚状、斑块状沉积物。PrPSc主要沉积于大脑皮质Ⅲ、Ⅳ、Ⅴ层 ,海马锥体细胞层 ,小脑皮质颗粒层。HE染色结果显示大脑皮质海绵样病变在接种后 40天出现 ,随着接种时间的延长而加剧。Westernblot检测显示PrPSc在接种后 40天即可检出 ,PrP总量和PrPSc含量随着接种时间的延长而增加。结论　随着接种时间延长 ,羊瘙痒因子 2 63K感染的金黄仓鼠脑中PrPSc沉积累及的范围、程度扩大 ,IHC检测脑组织中PrPSc的沉积早于临床症状的出现 ,甚至其它检测方法的检出。Aim To observe the characteristics of PrP Sc deposits in the hamsters' brains infected with scrapie 263K. Methods After challenged intracerebrally with scrapie 263K,the animals were sacrificed 20 ,40 ,50 ,60 and 70 day postinoculation. PrP Sc deposits,neuropathological changes and protease resistant PrP were analyzed by immunohistochemistry (IHC),HE stain and Western blot. Results Few PrP Sc deposits were firstly identified in the brain tissues 20 day postinoculation. Intracellular deposits of PrP Sc were observed in the animals 40 day postinoculation,with more widely distribution. Larger granular,as well as plaque like PrP Sc were seen in the brain tissues 50 and 60 day postinoculation,with extensive spongiform degeneration in that of 70 day. Histoblot of PrP Sc deposited largely in the layer Ⅲ,Ⅳ and Ⅴ of cerebral cortex,pyramidal layer of hippocampus and granular layer of cerebellum,but not in white matter. Spongiform degeneration was firstly observed in cerebral cortex of the animals 40 day inoculation,and aggravated along with the incubation period. Protease resistant PrP Sc were firstly detected in brain homogenates prepared from the hamsters 40 day postinoculation. Total amount of PrP and the amount of PrP Sc in brain tissues increased significantly with prolong of incubation. Conclusion Along with the incubation,more extensive PrP Sc deposits distribute in the brain tissues of the infected hamsters with scrapie strain 263K. PrP Sc in central nerve tissues identified with IHC appears much earlier than the onset of clinical manifestations,even earlier than that with other commonly used methods.

关 键 词：羊瘙痒因子263K感染 金黄仓鼠 脑 PrP^sc 动态沉积特点 免疫组化 海绵样病变 

分 类 号：S852.659.7[农业科学—基础兽医学]