Open AccessExistence of Functional α1A- and α1D- but No α1B-Adrenoceptor Subtypes in Rat Common Carotid Arteries
Author(s) -
Shigetoshi Chiba,
Miyoko Tsukada
Publication year - 2002
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.88.146
Subject(s) - methoxamine , phenylephrine , potency , carotid arteries , agonist , cannula , adrenergic receptor , pharmacology , endocrinology , medicine , chemistry , receptor , blood pressure , in vitro , biochemistry , surgery
Using the cannula inserting method, vasoconstrictor responses to alpha1-adrenoceptor agonists (noradrenaline [NA], phenylephrine [PE] and methoxamine [ME]) and effects of alpha1-adrenoceptor antagonists (WB4101, chloroethylclonidine [CEC] and BMY7378) were investigated in isolated and perfused rat common carotid arteries. The rank order of agonist potency and efficacy was NA = PE > ME. Either WB4101 or BYM7378 inhibited NA- and PE-induced constrictions in a dose-related manner. CEC did not inhibit the NA- and PE-induced responses. The ME-induced responses were also significantly blocked by either WB4101 or BMY7378. From these results, it is concluded that there are functional alpha1A- and alpha1D-adrenoceptor subtypes in rat common carotid arteries, but no functional alpha1B subtype.