Alterations in beta-adrenoceptor density on T-lymphocytes upon activation with interleukin-2 and phytohaemagglutinin.
Cultivation of human peripheral blood T-lymphocytes in the presence of interleukin-2 (IL-2) and phytohaemagglutinin (PHA) caused biphasic alterations in the beta 2-adrenoceptor density (Bmax) and cAMP content of these cells. The increase in Bmax after 18 h incubation with IL-2 and PHA was due to the expression of the receptors in a low-affinity state. The stimulatory effect of isoproterenol on adenylate cyclase activity and its effect on cAMP content remained unchanged, indicating uncoupling between the expressed receptors and regulatory Gs-proteins. The addition of phorbolmyristateacetate (PMA), a protein kinase C activator, also caused a biphasic change in beta 2-adrenoceptor density on the surface of the cells. The data point to the involvement of protein kinase C in the mechanism responsible for the increase and subsequent decrease in beta 2-adrenoceptor density seen after activation of T-lymphocytes.
Korichneva
I L
IL
Institute of Experimental Cardiology, Academy of Medical Sciences of the USSR, Moscow.
Tkachuk
V A
VA
D000262:Adenylyl Cyclases / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000032:analysis; D015536:Down-Regulation / Q000187:drug effects; D004347:Drug Interactions; D004789:Enzyme Activation / Q000187:drug effects; D019204:GTP-Binding Proteins / Q000378:metabolism; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects*; D010835:Phytohemagglutinins / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D015290:Second Messenger Systems / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007376:Interleukin-2; D010835:Phytohemagglutinins; D011943:Receptors, Adrenergic, beta; D005576:Colforsin; D006165:Guanylyl Imidodiphosphate; D000242:Cyclic AMP; D011493:Protein Kinase C; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D007545:Isoproterenol; D013755:Tetradecanoylphorbol Acetate