Paulo Marcos Zech Coelho; Leógenes Horácio Pereira*; Rômulo Teixeira de Mello
ABSTRACT
In this study, four compounds were utilized at the dose of 12.5mg/kg body weight, p.o., to treat Cebus monkeys experimentally infected with about 200 cercariae of Schistosoma mansoni (SJ strain), via transcutaneous route. The oograms performed with rectal snips, as well as stool examinations carried out periodically, showed no viable eggs of the parasite, from day 29 to 226post-treatment. The perfusion undertaken after killing the animals showed absence of worms in the treated monkeys, whereas 83 worms were recovered from the control, thus corroborating the results obtained by means of oograms and coproscopy. These results confirm the efficacy of 9-acridanone- hydrazones previously tested against the LE strain of S. mansoni. The low curative dose and apparent absence of toxicity render these dmgs an important therapeutic reserve, taking into consideration the reports on the resistance of S. mansoni to the modern drugs oxamniquine and praziquantel.
Keywords: Schistosoma mansoni. Cebus monkeys. Acridanone-hydrazone.
RESUMO
No presente trabalho, quatro compostos foram utilizados na dose de 12,5mg/kg de peso, por via oral, em macacos infectados transcutaneamente com cerca de 200 cercárias de Schistosoma mansoni. Os oogramas realizados com fragmentos de mucosa retal e os exames de fezes realizados, periodicamente, demonstraram a ausência de ovos viáveis do parasito a partir do 29- até o 226a dia pós-tratamento. A perfusão, apôs sacrifício dos animais tratados, não detectou vermes, enquanto que do macaco cotztrole 83 vermes foram recuperados, confirmando assim os resultados dos oogramas e da coproscopia. Estes resultados confirmam a eficácia das 9-acridanonas- hydrazonas já observada anteriormente contra a cepa LE de S. mansoni. A baixa dosagem curativa e aparente ausência de toxicidade colocam estas drogas como uma reserva terapêutica importante, tendo em vista o relato de resistência do S. mansoni às drogas modernas oxamniquína e praziquantel.
Palavras-chave: Schistosoma mansoni. Macacos Cebus. Acridanona-hidrazonas.
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Adress to correspondence:
Prof. Paulo Marcos Zech Coelho,
Depto de Parasitologia.
ICB/UFMG/Caixa Postal 486,
30161-970
Belo Horizonte, MG.
Recebido para publicação em 24/08/94.
* Deceased 6 February, 1994
Departamentos de Parasitologia, Instituto de Ciências Biológicas, e de Análises Clínicas eToxicológicas, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG. This study was supported in part by CNPq, FAPEMIG, PRPq/UFMG, Brazil, and by WHO, Switzerland.
