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Aminopeptidase activity in the brains of mice with chronicToxoplasma gondii infections

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Aminopeptidase activity on β-naphthylamide (NA) substrates was assayed in brain extracts from normal andToxoplasma gondii-infected mice at 4 months postinfection. Correlations of levels of aminopeptidase activity,Toxoplasma-specific antibody production, and the number of brain cysts were studied in normal andToxoplasma-infected mice. TheToxoplasma-specific antibody and the formation of cysts were markedly enhanced in the parasite-infected mice. The highest levels of activity for the NA substrates tested were observed in normal mice. In contrast, the activity levels were significantly lower inT. gondii-infected mice than in the corresponding normal mice. These results suggest an association between chronic toxoplasmosis and aminopeptidase activity in the parasite-infected host brain.

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Correspondence to S. Akao.

Additional information

Held as paper during the 6th Japanese-German Cooperative Symposium on Protozoan Diseases München, 21–25th Sept. 1987

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Akao, S., Yamakami, K., Nishiyama, M. et al. Aminopeptidase activity in the brains of mice with chronicToxoplasma gondii infections. Parasitol Res 75, 186–188 (1989).

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  • Normal Mouse
  • Antibody Production
  • Toxoplasmosis
  • Brain Extract
  • Aminopeptidase Activity