Alterations of beta-adrenoceptors on human leukocyte subsets induced by dynamic exercise: effect of prednisone.
1. In order to investigate exercise-induced changes of beta 2-adrenoceptors on human leukocyte subsets, beta-adrenoceptor density was determined as specific binding of [125I]-iodocyanopindolol to granulocytes, monocytes, B and T lymphocytes of six subjects immediately before and after exercise and after 30 min of rest. 2. A 10 min graded bicycle exercise with a workload of 50-250 W caused a transient increase of granulocytes, monocytes, B and T cells of about 32, 43, 120 and 25%, respectively. 3. While the number of beta 2-adrenoceptors in granulocytes remained unchanged, beta-adrenoceptor densities in B cells, T cells and monocytes increased from pre-exercise mean values of 2730, 870 and 2400 binding sites/cell to 3500, 1230 and 3220 binding sites/cell, respectively, under physical stress. The rise in receptor numbers was accompanied by an enhanced isoprenaline-stimulated cyclic AMP formation in unfractionated mononuclear leukocytes (MNL) of about 26% as well as by a 2-3-fold increase in plasma catecholamine levels. Cell concentrations, beta 2-adrenoceptor numbers and adrenergic responsiveness returned to normal after 30 min rest. 4. Administration of 60 mg prednisone 2 h before exercise resulted in granulocytosis and lymphopenia with a preponderant effect on the exercise-induced rise in B cells and monocytes. Corticosteroids showed no effect on stress-induced changes of beta 2-adrenoceptors and responsiveness. 5. It is concluded that exercise-induced increases in beta 2-adrenoceptor density and adrenergic responsiveness of unfractionated MNL are caused by a release of receptor-enriched cells into the circulation, particularly of B lymphocytes and monocytes which carry the highest beta 2-adrenoceptor density.
Ratge
D
D
Department of Clinical Chemistry, Robert-Bosch-Hospital, Stuttgart, FR Germany.
Wiedemann
A
A
Kohse
K P
KP
Wisser
H
H
D000328:Adult; D001402:B-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D002395:Catecholamines / Q000097:blood; D000242:Cyclic AMP / Q000097:blood; D015444:Exercise; D006098:Granulocytes / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D020120:Iodocyanopindolol; D007545:Isoproterenol / Q000494:pharmacology; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D010869:Pindolol / Q000031:analogs & derivatives; D011241:Prednisone / Q000494:pharmacology*; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism
D002395:Catecholamines; D011943:Receptors, Adrenergic, beta; D020120:Iodocyanopindolol; D010869:Pindolol; D000242:Cyclic AMP; D007545:Isoproterenol; D011241:Prednisone