Metabolic and Circulatory Responses to Selective Adrenergic Stimulation and Blockade
Selected cardiovascular and metabolic responses to highly specific alpha- and beta- adrenergic stimulation and blockade were studied in eight patients. Selective beta-adrenergic stimulation with isoproterenol produced a rise in the level of plasma FFA concomitant with its cardio-accelerator effect. Both of these responses were inhibited by the prior administration of the specific beta-adrenergic blocking agent, propranolol. Selective alpha-adrenergic stimulation with methoxamine increased systemic arterial pressure but produced no metabolic changes. Alpha-adrenergic blockade with phenoxybenzamine did not alter the circulatory or metabolic responses to isoproterenol. These findings support the hypothesis that the adrenergic influence over the level of circulating FFA is mediated by the beta-adrenergic receptors. Structure-activity relationships of the four agents used in this study have been examined.
- © 1966 American Heart Association, Inc.