Abstract
Isoamyl acetate, n-butyl acetate, n-amyl acetate and n-propyl acetate produced contractions of the isolated ileum of the guinea-pig. These were inhibited by atropine, procaine and by cooling. These acetates and also s-butyl, t-butyl and n-octyl acetate behaved as inhibitors of acetylcholine at 14 ± 1°. The acetylcholine content in the organ bath fluid increased after 60 min incubation of the ileum with isoamyl acetate. The results indicated that the agonistic acetates produced contraction of ileum through the liberation of acetylcholine from the cholinergic nerve-endings. All the acetates behaved as inhibitors of acetylcholine when they combined with the acetylcholine receptor on the muscle.