Effect of diethylcarbamazine on Setaria cervi in vitro.

Diethylcarbamazine (DEC) produced an initial stimulation followed by depression of the movements of the intact worm and nerve-muscle preparation of Setaria cervi. The effective concentration of DEC was reduced to one hundredth in the nerve-muscle preparation as compared to the whole worm, suggesting that the cuticular barrier is highly effective in preventing the penetration of the drugs. The depressant effect of DEC was concentration dependent and was not reversed even after repeated changes of the bath fluid. The worms consumed 7.7 mg +/- 0.2 glucose/g wet weight/hr. The consumption of glucose was directly proportional to its motor activity; it increased during the stimulant phase with low doses of DEC and decreased during the depressant phase.