Open AccessEffect of /-ephedrine on cholinergic neurotransmission in the isolated guinea pig ileum.
Author(s) -
Ryōichi Yamamoto,
Chikako Nuki,
Hideyuki Komidori,
Koichiro Takasaki
Publication year - 1989
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.50.511
Subject(s) - yohimbine , ephedrine , endocrinology , cholinergic , medicine , chemistry , acetylcholine , clonidine , prazosin , reserpine , sulpiride , pharmacology , receptor , biology , antagonist
In the isolated guinea pig ileum, the effects of I-ephedrine on the twitch response to field stimulation were investigated in the presence of propranolol. Ephedrine and clonidine inhibited the twitch response but not the contraction to exogenous acetylcholine. The inhibitory effect of clonidine was significantly diminished by yohimbine pretreatment. However, the inhibitory effect of ephedrine was not influenced by yohimbine, sulpiride or 6-hydroxydopamine (6-OHDA) pretreatment. Most of this action of ephedrine appeared to be cholinergic prejunctional in nature, but unrelated to activation of prejunctional alpha 2-adrenoceptors and dopamine sensitive receptors on the cholinergic nerves in this preparation.