Differences in the applicability of the easson-stedman hypothesis to the alpha 1- and alpha 2-adrenergic effects of phenethylamines and imidazolines.
The enantiomers of 2-(3,4, alpha-trihydroxybenzyl)imidazoline and the corresponding desoxy derivative, 2-(3,4-dihydroxybenzyl)imidazoline, were evaluated at alpha 1- and alpha 2-adrenergic receptors to test the applicability of the Easson-Stedman hypothesis to the imidazoline class of alpha-adrenergic agonists. A series of closely related phenethylamines was included for comparison. The Easson-Stedman hypothesis states that optically active adrenergic agonists possessing an asymmetric hydroxyl-substituted benzylic carbon atom will have the following relative potencies: R(-) greater than S(+) = desoxy. While the phenethylamines were found to adhere to the Easson-Stedman hypothesis at both alpha 1- and alpha 2-adrenergic receptors, the optically active imidazolines did not. These findings further support our previous observations that the phenethylamines and imidazolines may interact differently with alpha-adrenergic receptors.
D000818:Animals; D006168:Guinea Pigs; D007093:Imidazoles / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010627:Phenethylamines / Q000494:pharmacology*; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
D007093:Imidazoles; D010627:Phenethylamines; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D009638:Norepinephrine