Capillaria hepatica-induced hepatic fibrosis in rats: paradoxical effect of repeated infections

Revista da Sociedade Brasileira de Medicina Tropical

Andrade, Zilton A.¹  UFBA¹  FIOCRUZ, Bahia¹  Oliveira, Ludmila¹  Souza, Márcia Maria de¹  FIOCRUZ¹ 

关键词: Capillaria hepatica;    Hepatic fibrosis;    Repeated infections;   

DOI  :  10.1590/S0037-86822004000200001

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Medicina Tropical

【 摘 要 】

Multiple exposures to parasitic agents are considered an important factor in the genesis of the most severe forms of the diseases they cause. Capillaria hepatica-induced septal fibrosis of the liver in rats usually runs without signs of portal hypertension or hepatic failure. After determining the hepatic profile of 15 animals during the course of a single infection, we submitted 20 rats to multiple Capillaria hepatica infections to determine whether repeated exposures would augment fibrosis production, transforming septal hepatic fibrosis into a true cirrhosis. Ten single-infection rats served as controls. A total of 5 exposures, with 45-day intervals, were made. Histological changes were followed by means of surgical liver biopsies, collected prior to infection and to each re-infection. Functional changes were minimal and transient. Although a slight recrudescence of fibrosis was observed after the first two re-infections and when the single-infected control group was re-infected at the end of the experiment, subsequent re-infections failed to increase the amount of fibrosis. On the contrary, there occurred quantitative and qualitative evidence of collagen degradation and suppression of parasite development. These paradoxical results are in keeping with the hypothesis that a complex immunological modulation participates in the mechanism of hepatic fibrosis induced by Capillaria hepatica infection in rats.

【 授权许可】

Unknown