Capillaria hepatica-induced septal fibrosis in rats: a contribution to the study of liver fibrogenesis Contribuição para o estudo da fibrogenesis hepática em ratos infectados com Capillaria hepatica

• Published in: Revista da Sociedade Brasileira de Medicina Tropical
• Main Authors: Valter Lucas Chaves Barbosa, Zilton de Araújo Andrade
• Format: Article in Journal/Newspaper
• Language: English
• Published: Sociedade Brasileira de Medicina Tropical (SBMT) 2010
• Subjects: Fibrose hepática; Patogenia; Capillaria hepatica; Hepatic fibrosis; Pathogenesis; Arctic medicine. Tropical medicine; RC955-962; Arctic
• Online Access: https://doi.org/10.1590/S0037-86822010000500006; https://doaj.org/article/a3a6b68842da4cccb8abe0e20c43605f

INTRODUCTION: Septal fibrosis of the liver regularly develops in rats infected with the nematode Capillaria hepatica. Curative treatment of the infection prevents the development of septal fibrosis when intervention occurs up to postinfection day (PID) 15, but not later. The present investigation aimed to demonstrate which parasitic factors are present when the process of septal fibrosis can no longer be prevented by curative treatment. METHODS: Wistar rats were infected with 600 embryonated eggs of C. hepatica administered by gavage and treated with ivermectin and mebendazole in separate groups at PIDs 10, 12, 15, 17 or 20. Rats from each group and their nontreated controls, were killed and examined 40 days after the end of treatment. RESULTS: Findings by PID 15 were compatible with the stage of complete maturation of infection, when worms and eggs were fully developed and a complex host-parasite multifocal necroinflammatory reaction showed greater intensity, but with no signs of septal fibrosis, which appeared from PID 17 onward. CONCLUSIONS: Since the worms spontaneously died by PID 15, not only septal fibrosis production, but also its maintenance and further development appeared dependent on the presence of eggs, which were the only parasitic factor remaining thereafter. INTRODUÇÃO: A fibrose septal do fígado se desenvolve regularmente em ratos infectados pelo nematódeo Capillaria hepatica. O tratamento curativo da infecção, feito antes do 15º dia da infecção, mas não mais tarde, impediu o aparecimento da fibrose septal. O presente trabalho procura verificar qual o estado do parasitismo aos 15 dias da infecção, crucial para patogenia da fibrose septal. MÉTODOS: Ratos foram infectados por via digestiva com 600 ovos embrionados de C. hepatica e tratados com Ivermectina e mebendazol, em grupos separados, aos 10, 12, 15, 17 ou 20 dias após a infecção. O animal de cada grupo e seus respectivos controles foram mortos e examinados aos 40 dias após o fim do tratamento. RESULTADOS: Os achados aos 15 dias da infecção ...