Article,
The pharmacological profile of the acetylcholine response of a crustacean muscle
J Exp Biol, (January 1980)
Abstract
A pharmacological analysis was made of the depolarizing acetylcholine (ACh) response found on the gastric mill 1 muscles of the crabs Cancer
pagurus, Cancer irroratus and Cancer borealis. Acetylcholine, carbamylcholine, trimethylammonium, nicotine, and
dimethyl-4-phenyl-piperazinium were effective in producing contractures and depolarizations in these muscles. No response to decamethonium, suberyldicholine, acetyl-/?-methylcholine, carbamyl-^-methylcholine, pilo- carpine and oxotremorine could be detected.
High concentrations of muscarinic agonists (io~4 to io~3 M) potentiated and prolonged the ACh iontophoretic response. When the acetylcholinest- erase activity was inhibited with neostigmine, or when the response was elicited with carbamylcholine, muscarinic agonists partially inhibited the response.
ACh responses were most effectively blocked by vertebrate nicotinic ganglionic antagonists, including dihydro-/?-erythroidine, pempidine, and mecamylamine.
a-Bungarotoxin was without effect on the ACh response.
