title: Speed of onset of pharmacodynamic activity of propranolol, practolol, oxprenolol and metoprolol after intravenous infection in man.
abstract: 1 The speed of onset of the pharmacodynamic activity of intravenous propranolol, practolol, oxprenolol and metoprolol was determined, using attenuation of isoprenaline-induced tachycardia as the end-point, in 16 patients with clinically coronary heart disease. 2 Antagonism was evident within 15 s of injection into the central circulation of all four drugs. The time to maximum attenuation of isoprenaline tachycardia was significantly more rapid with propranolol and oxprenolol than with practolol and metoprolol.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008790:Metoprolol / Q000494:pharmacology; D008875:Middle Aged; D010096:Oxprenolol / Q000494:pharmacology; D011217:Practolol / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000319:Adrenergic beta-Antagonists; D010096:Oxprenolol; D011433:Propranolol; D008790:Metoprolol; D011217:Practolol