POTENCY AND SELECTIVITYin vitroOF COMPOUNDS RELATED TO ISOPRENALINE AND ORCIPRENALINE ON β‐ADRENOCEPTORS IN THE GUINEA‐PIG

Open Access
Publisher Website
Google Scholar
Abstract
1 Amines related in structure to either isoprenaline (catechol series) or orciprenaline (resorcinol series) were examined for activity on isolated trachea (relaxation), atria (chronotropic action) and perfused hind-limb (vasodilatation) of the guinea-pig. 2 Compounds with a resorcinol nucleus were less potent on all three preparations but more selective for trachea than were compounds with a catechol nucleus. 3 In both catechol and resorcinol compounds potency on trachea was enhanced by and selectivity for trachea was favoured by substitution of a p-OH phenyl group in the N-isopropyl, or by replacement of the N-isopropyl with an N-t-butyl, with or without a p-OH phenyl group. 4 Most of the compounds, particularly the resorcinols, had much lower potencies, relative to isoprenaline, on hind-limb than on trachea. 5 Some of the problems associated with the quantitative measurement of selectivity and with sub-classification of β-adrenoceptors are discussed.
Keywords