[Chronobiological studies on effect of cyclosporin A (CsA) against adult male worms of Schistosoma mansoni in vitro].
OBJECTIVE
To study the action mode of cyclosporin A (CsA) against Schistosoma mansoni in vitro.


METHODS
MF1 mice were infected with Schistosoma mansoni cercariae for 6 weeks when the adult worms were recovered by portal perfusion. The male worms of S. mansoni recovered were exposed to varying concentrations of CsA at 8, 16, and 24 h in vitro. Drug induced damage to the male worm surface was chrono-biologically observed throughout these experiments by SEM.


RESULTS
After the male worms of S. mansoni were incubated with 1 microgram/ml CsA for 8-24 h, the tegument showed swelling of ridges with appearance of holes on their surface and detachment of a part of spines. The above damage of the tegument became more evident in male worms after incubation with 10, 15, 20 micrograms/ml CsA for 8-24 h. Moreover, incubation of male worms with 25 micrograms/ml CsA for 8-24 h resulted in significant deformation and disruption of tegument, rupture of ridges and detachment of spines. The tegumental damage of male worms of S. mansoni was dose- and time-dependent.


CONCLUSIONS
The antischistosomal action of CsA is direct, the schistosome tegument appears to be the main site for CsA attack.
Liu
J
J
Department of Parasitology, Medicl College of Shihezi University, Shihezi 832002.
Chappell
L H
LH
D000818:Animals; D002909:Chronobiology Phenomena; D016572:Cyclosporine / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008855:Microscopy, Electron, Scanning; D012550:Schistosoma mansoni / Q000187:drug effects / Q000648:ultrastructure*; D012556:Schistosomicides / Q000494:pharmacology*
D012556:Schistosomicides; D016572:Cyclosporine