Premium
Relevance of selectivity and non‐selectivity in beta‐adrenoceptor blocking drugs.
Author(s) -
Bonelli J
Publication year - 1982
Publication title -
british journal of clinical pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.216
H-Index - 146
eISSN - 1365-2125
pISSN - 0306-5251
DOI - 10.1111/j.1365-2125.1982.tb01911.x
Subject(s) - metoprolol , propranolol , phentolamine , isoprenaline , tachycardia , atropine , chronotropic , pharmacology , heart rate , chemistry , medicine , endocrinology , stimulation , blood pressure
1 The heart rate responses to increasing doses of isoprenaline (n = 6) (during infusion with atropine 0.5 mg/min i.v.) and noradrenaline (n = 5), (during infusion with phentolamine 160 mg/h i.v.) were recorded before and after the intravenous administration of propranolol (15 mg) or metoprolol (15 mg). 2 In the doses used, metoprolol was less potent than propranolol in antagonizing isoprenaline‐induced tachycardia, during atropine infusion. 3 In volunteers treated with phentolamine both metoprolol and propranolol produced similar inhibition of noradrenaline‐induced tachycardia, indicating comparable beta 1‐ adrenoceptor blockade in the doses used. 4 The fact that the shift of the dose‐response curve of isoprenaline‐induced tachycardia was smaller after metoprolol than after propranolol supports the hypothesis that beta 2‐adrenoceptors are present in the heart.