| Abstract: | The susceptibility of Schistosoma japonicum ofdifferent developmental stages to praziquantel hasbeen studied by several methods. The results showedthat praziquantel was more effective against 3-h oldschistosomule (d 0) and 2&day old t0 42-day old adultworms (d 28 to d 42), but had no effect on 3-dayold t0 21-day old schistosomules (d 3 to d 21). Sincepraziquantel could be excreted and secreted fromthe skin of mouse after administration, the drugexhibited a prophylactic effect when it was given tothe host before infectiom The susceptibility of12-h old t0 48-h old schistosomules to praziquantelwas much lower than that of 3-h old schistosomule.This difference may be ascribed to varied immuno-reaction on the worm surface within 2 days afterinfection. Besides, d-21 worms lodging in rabbitswith higher specific antibody level could be killedby praziquantel. |
