title: Beta adrenoceptors of human red blood cells, determination of their subtypes.
abstract: The characteristics of beta adrenergic receptors of human erythrocyte membranes were investigated using (-)125iodocyanopindolol as a radioligand. Inhibition of (-)125iodocyanopindolol specific binding was checked using either atenolol and metoprolol as beta 1 selective antagonists or ICI 118551 and IPS 339 as beta 2 selective antagonists. The results showed non linear Hofstee's plots suggesting that both beta 1 and beta 2 adrenergic receptors are present. Analysis of the data yielded a beta 1/beta 2 adrenergic receptor ratio of approximately 33/67. Thus it is concluded that beta 2 subtype is predominant on human erythrocyte membranes.
mesh_terms: D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D004912:Erythrocytes / Q000032:analysis*; D006801:Humans; D020120:Iodocyanopindolol; D007700:Kinetics; D010869:Pindolol / Q000031:analogs & derivatives / Q000378:metabolism; D011869:Radioligand Assay; D011943:Receptors, Adrenergic, beta / Q000032:analysis*
chemical_list: D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D011943:Receptors, Adrenergic, beta; D020120:Iodocyanopindolol; D010869:Pindolol