IMAMURA Masakatsu Sapporo Med. Coll., Associate Professor, 医学部, 助教授 (30045398)
MORI Michio Sapporo Med. Coll., Professor, 医学部, 教授 (00045288)
URASAWA Shozo Sapporo Med. Coll., Professor, 医学部, 教授 (00045379)
HASHIMOTO Nobuo Hokkaido Univ., Fac. of Veter. Med., Professor, 獣医学部, 教授 (60082103)
|Budget Amount *help
¥4,400,000 (Direct Cost : ¥4,400,000)
Fiscal Year 1987 : ¥400,000 (Direct Cost : ¥400,000)
Fiscal Year 1986 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1985 : ¥3,500,000 (Direct Cost : ¥3,500,000)
This study was undertaken to reveal pathogenicity of HFRS related virus, the mode of transmission of the virus and the sensitivity of rats to the virus by an immunohistological technique. Accordingly, neonatal and adult rats were Experimentally infected with SR-11 strain. Viral antigen was detected in various organs from those animals by ABC methods.
1. In the preliminary study, infected Vero E-6 cells with SR-11 strain was examined by immuno-electron microscopical procedures. Viral antigen was detected in inclusion bodies and small vesicles in the cytoplasm, however, viral particles were not observed in these structures. From this study, the inclusions are considered to be by-products of viral proliferation.
2. Suckling rats (less than 24 hr) were inoculated by intraperitoneal (i.p.) route with 10^3 FFU of SR-11 strain. They showed central nervous symptoms, such as paralysis and convulsion, and died by four weeks. Viral antigen was detected in lung, brain, kidney, spleen, liver, heart a
nd salivary gland for a long time, but no antigen was detected in intestine.
3. Suckling rats and adult rats were inoculated by i.p. or nasal route with sr-11 strains and 50% infectious dose (ID_<50>) were calculated according to production of the antibodies. The ID_<50> values in contrasting age groups or inoculation routes did not show any significant differences.
4. Suckling rats inoculated by i.p. route with SR-11 strain showed increasing positive rates in both antigen and antibody depending on the increase of recieving viral dose. However, viral antigen was limited in the lungs from suckling rats inoculated by nasal route and adult rats inoculated by i.p. route only after administration of high viral dose. Although the production of antibodies was observed, no viral antigen was detected in any organs.
5. Antibody conversions were observed in 2 of 4 suckling rats which were kept with infected suckling rats. Furthermore, viral antigen was detected in the lung tissues from the sero-converted animals. Less