[Dependence of kinetic constants of intact human lymphocyte beta2-adrenoreceptors on the nature of the radioligands used].
An analysis of human peripheral blood intact mononuclear lymphocyte beta 2-adrenoreceptors showed that the hydrophilic radioligand 3H-CGP-12177 binds at various temperatures only to surface receptors. The density of receptors as determined by the binding of the lipophilic antagonist 125I-CYP at 37 degrees C is 2 times as high as that at 4 degrees C. The affinity of lymphocyte beta 2-adrenoceptors for 1-isoproterenol measured by the labeled ligand displacement at low (4 degrees C) temperatures is by two or three orders of magnitude higher than that at 37 degrees C. The thiol-alkylating agent, N-ethylmaleimide (NEM) causes oppositely directed changes in the density of beta 2-adrenoceptors on intact lymphocytes depending on their original density. NEM increases the affinity of beta 2-adrenoreceptors for the hormone (1.5-12-fold). The state and regulation of human peripheral blood lymphocyte beta 2-adrenoreceptors depend on the hormonal status of patients at the moment of blood sample collection.
Krasnikova
T L
TL
Korichneva
I L
IL
Radiukhin
V A
VA
D000319:Adrenergic beta-Antagonists; D000526:Alprenolol; D001667:Binding, Competitive; D005033:Ethylmaleimide; D006801:Humans; D007545:Isoproterenol; D007700:Kinetics; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D010869:Pindolol / Q000031:analogs & derivatives; D011412:Propanolamines; D011869:Radioligand Assay; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*; D013696:Temperature
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011943:Receptors, Adrenergic, beta; C047975:cyanopindolol; D000526:Alprenolol; D010869:Pindolol; D007545:Isoproterenol; D005033:Ethylmaleimide; C033394:CGP 12177
Zavisimost' kineticheskikh konstant beta2-adrenoretseptorov intaktnykh limfotsitov cheloveka ot prirody primeniaemykh radioligandov.