Caldas, SérgioSantos, Fabiane Matos dosLana, Marta deDiniz, Lívia de FigueiredoCoelho, George Luiz Lins MachadoVeloso, Vanja MariaBahia, Maria Terezinha2014-11-102014-11-102008CALDAS, S. et al. Trypanosoma cruzi : acute and long-term infection in the vertebrate host can modify the response to benznidazole. Experimental Parasitology, v. 118, p. 315-323, 2008. Disponível em: <http://www.sciencedirect.com/science/article/pii/S0014489407002378>. Acesso em: 20 ago. 2014.0014-4894http://www.repositorio.ufop.br/handle/123456789/3746We analyzed the influence of Trypanosoma cruzi maintenance in different hosts (dog and mouse) on its susceptibility to benznidazole treatment. Five T. cruzi stocks were isolated from dogs inoculated with Be-62 or Be-78 strain (both sensitive to benznidazole) 2–10 years ago, and the benznidazole sensitivity was then determined using the mouse as experimental model. The different T. cruzi stocks obtained from long-term infected dogs showed 50–90% drug resistance right after isolation. However, maintenance of these T. cruzi stocks in mice, by successive blood passages (2.5 years), led to either a decrease or stability of the drug resistance pattern and an increase in parasite virulence. We also demonstrated the effectiveness of the induction of parasitemia reactivation by cyclophosphamide immunosuppression in the evaluation of the response to the specific drug treatment.en-USTrypanosoma cruziChagas diseaseDrug resistanceChemotherapyCure controlArtigo publicado em periodicoO periódico Experimental Parasitology concede permissão para depósito deste artigo no Repositório Institucional da UFOP. Número da licença: 3483170557595.https://doi.org/10.1016/j.exppara.2007.08.016