title: Pathogenesis of scrapie: agent multiplication in brain at the first and second passage of hamster scrapie in mice.
abstract: The intracerebral (i.c.) injection of mice with a particular source of hamster passaged scrapie produced disease after an incubation period of 325 +/- 6 days (mean +/- s.e.). The incubation period at the second i.e. passage in mice was reduced to 149 +/- 2 days. Studies were made of the dynamics of agent replication at 1st and 2nd passages in mice. At first passage, there was a 'zero phase' lasting about 175 days, when no infectious agent was detected in brain (or spleen), followed by a period of agent replication which lasted 150 days. At second passage, there was no significant 'zero phase' and agent replication occupied the whole of the incubation period. The occurrence of a 'zero phase' on interspecies passage of scrapie is discussed in relation to other reports of a 'zero phase' in mouse passaged scrapie.
mesh_terms: D000818:Animals; D001921:Brain / Q000382:microbiology; D006224:Cricetinae; D005260:Female; D008297:Male; D051379:Mice; D011328:Prions / Q000254:growth & development*; D012608:Scrapie / Q000382:microbiology* / Q000635:transmission; D012756:Sheep; D013045:Species Specificity; D013154:Spleen / Q000382:microbiology; D013997:Time Factors
chemical_list: D011328:Prions