Measurement of beta-adrenergic receptors on lymphocytes in normal subjects and asthmatics in relation to beta-adrenergic hyperglycaemic response and bronchial responsiveness.
The numbers of beta-adrenergic receptors on lymphocytes in normal subjects and asthmatic patients were measured by the use of [125I]hydroxybenzylpindolol. The numbers of beta-adrenergic receptors per lymphocyte in normal subjects, drug-free asthmatics and patients taking beta-stimulants were 1146 +/- 98, 845 +/- 114 and 582 +/- 47 sites/cell (mean +/- SE), respectively. The differences were statistically significant (P less than 0.05) among these groups, while no statistically significant differences were found in dissociation constants. A 42% decrease in the number of beta-adrenergic receptors per lymphocyte after administration of 6 mg/day of terbutaline for 7 days was noted in four volunteers. There was significant correlation (r = 0.68, P less than 0.01) between the number of beta-adrenergic receptors per lymphocyte and the percentage increase in blood sugar 20 min after subcutaneous injection of 4 micrograms/kg epinephrine. There was also significant correlation (r = 0.78, P less than 0.005) between the number of beta-adrenergic receptors per lymphocyte and the respiratory threshold for acetylcholine. These results suggest that beta-blockade and bronchial hypersensitivity in asthmatic patients may in part be due to a decreased number of beta-adrenergic receptors.
D000109:Acetylcholine / Q000008:administration & dosage; D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000403:Airway Resistance / Q000187:drug effects; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy / Q000276:immunology*; D001985:Bronchial Provocation Tests; D004306:Dose-Response Relationship, Immunologic; D004837:Epinephrine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000139:chemically induced / Q000276:immunology*; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011941:Receptors, Adrenergic / Q000032:analysis*; D011943:Receptors, Adrenergic, beta / Q000032:analysis* / Q000187:drug effects; D013726:Terbutaline / Q000008:administration & dosage
D000305:Adrenal Cortex Hormones; D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D013726:Terbutaline; D000109:Acetylcholine; D004837:Epinephrine