Neuromuscular transmission in nematode parasites and antinematodal drug action.

Some anthelmintic drugs interfere selectively with nematode neuromuscular transmission. These drugs include: the nicotinic agonists, e.g. levamisole, the gamma-amino butyric acid agonist piperazine, and the avermectins which open Cl- channels. The physiology and pharmacology of neuromuscular transmission in nematodes is reviewed and the actions of antinematodal drugs which interfere with the transmission described. The results of experiments on the large porcine-intestinal nematode parasite, Ascaris suum, form the basis of the account presented but experiments on other nematodes suggest that these observations may be generalized. Results of some experiments on the small free living nematode Caenorhabditis elegans are also included.