[Pathological changes in the livers of rabbits infected with schistosome cercariae and treated with artemether or praziquantel in the early stage of infection].

When rabbits infected with Schistosoma japonicum cercariae for 7 d were treated ig with artemether (Art) 30 mg.kg-1, and repeated at 1-wk intervals (i.e. on d 14, 21, 28 after infection) for 4 times, dead worms were found in the liver sections, but no egg or egg granuloma was detected. In infected rabbits treated repeatedly with the above-mentioned dosage of Art at 2-wk intervals (i.e. on d 21, 35, 49) after the first dosing on d 7 after infection, few eggs and egg granulomas were seen occasionally. In another experiment, praziquantel (Pra) 40 mg.kg-1 was given ig to rabbits on d 21 after infection and the same dosage was administered repeatedly at 1- or 2-wk intervals for 2 times, the numbers of eggs and egg granulomas detected in the liver sections of these 2 groups were much less as compared with the control. In the latter group treated at 2-wk intervals, only degenerated eggs and egg granulomas were detected occasionally in the liver sections. The results indicate that if Art or Pra was given to rabbits in the early stage after infection, no apparent or only slight damage of the liver induced by the eggs was seen due to the fact that most or even all of the female worms were killed.