Effects of drugs on beta-adrenergic receptors on human lymphocytes.
The density of beta-adrenergic receptors has been determined on membranes prepared from lymphocytes of normal human volunteers. Long-term administration of propranolol resulted in an increase in the density of receptors, whereas administration of the agonists ephedrine and terbutaline elicited a marked decrease in the density of receptors. These changes may explain the delayed side effects observed when propranolol administration is abruptly discontinued and the decreased efficacy that occurs during long-term administration of an agonist. In other experiments, pindolol, an antagonist with intrinsic sympathomimetic activity, was administered to normal subjects. A marked decrease in the density of receptors occurred within 1 day of administering pindolol. This effect persisted beyond the time at which pindolol administration was discontinued.
D000328:Adult; D000818:Animals; D004809:Ephedrine / Q000494:pharmacology; D006801:Humans; D008214:Lymphocytes / Q000032:analysis / Q000187:drug effects*; D010869:Pindolol / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D013726:Terbutaline / Q000494:pharmacology
D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D011433:Propranolol; D010869:Pindolol; D004809:Ephedrine; D013726:Terbutaline