Effect of praziquantel on glycogen content and [1-14C]glucose uptake in Schistosoma japonicum

When pairs of Schistosoma japonicum were exposed to culture medium containing praziquantel 1 or 10 microg/ml for 4 h, the glycogen content, [1-14C]glucose uptake, and incorporation of [1-14C]glucose into the glycogen were markedly decreased. Male schistosomes seemed to be more affected. After bisexual worms had been maintained in praziquantel 1 and 10 microg/ml for 4 h, and then transferred to drug-free culture medium for 4-18 h, the glycogen content and [1-14C]glucose uptake of female worms recovered promptly. In male worms the changes caused by praziquantel 1 microg/ml were reversible, while those caused by 10 microg/ml were not. Infected mice were given intragastrically praziquantel 20 mg/kg. After 2-4 h the glycogen content of the bisexual worms decreased markedly, but recovered in 48 h. After ig 100-300 mg/kg, no apparent recovery of glycogen content was seen 72 h later. When the worms perfused out from the mice 8 h after ig 100-300 mg/kg were maintained in vitro, the glycogen conent, [1-14C]glucose uptake and incorporation of [1-14C]glucose into the glycogen of the female worms could recover, but the recovery was not significantly in male worms.