Pharmacological analysis of atypical beta-adrenoceptors in the guinea pig gastric fundus using the beta(3)-adrenoceptor antagonist bupranolol.
Atypical beta-adrenoceptor-mediated relaxations to catecholamines (isoprenaline, noradrenaline and adrenaline) and beta(3)-adrenoceptor agonists, BRL37344 [(R*, R*)-(+/-)-4-[2-[(2-(3-chlorophenyl)-2-hydroxyethyl)amino]-propyl]phen oxyacetic acid sodium salt] and CGP12177A [(-)-4-(3-t-butylamino-2-hydroxy- propoxy)benzimidazol-2-one] in guinea pig gastric fundus were investigated. The five agonists induced concentration-dependent relaxation of the gastric fundus. In the presence of both atenolol and butoxamine only small rightward shifts of the concentration-response curves to these agonists were observed. Under this condition, however, bupranolol caused a concentration-dependent rightward shift of the concentration-response curve to catecholamines and beta(3)-adrenoceptor agonists. Schild plot analyses of bupranolol against these agonists gave pA(2) values of 6.08 (isoprenaline), 6. 04 (noradrenaline), 5.90 (adrenaline), 6.50 (BRL37344) and 5.80 (CGP12177A), respectively. These results clearly suggest that the existence of functional atypical beta-adrenoceptors in the guinea pig gastric fundus and the relaxation of these agonists in this tissue are mediated via atypical beta-adrenoceptors. Copyright Copyright 1999 S. Karger AG, Basel[1]References
- Pharmacological analysis of atypical beta-adrenoceptors in the guinea pig gastric fundus using the beta(3)-adrenoceptor antagonist bupranolol. Horinouchi, T., Koike, K. Pharmacology (1999) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg