[Scanning electron microscope observation on the tegumental surface alterations of Schistosoma japonicum induced by praziquantel at different developmental stages].

The in vitro effect of praziquantel on tegument of Schistosoma japonicum of different developmental stages has been studied using scanning electron microscopy. The results indicated that no or only a slight tegument damage induced by praziquantel was observed in 3 day to 14 day old schistosomules, while in d_0, d_(21), d_(28), d_(28) and d_(42) parasites a moderate or severe tegument damage could be seen. Similar results were obtained in in vivo test. The significance of tegument of different developmental stages of schistosomes caused by praziquantel has been discussed briefly.