title: Beta-adrenoceptor changes in human lymphocytes, induced by dynamic exercise.
abstract: In 10 healthy volunteers the effects of acute increases in concentrations of catecholamines in plasma induced by dynamic exercise (on a bicycle for 15 min at 80% of maximum heart rate) on lymphocyte beta 2-adrenoceptor density (determined by (+/-)-125iodocyanopindolol binding) and -responsiveness (determined by cyclic AMP responses to 10 mumol/l isoprenaline) were investigated. Immediately after exercise plasma catecholamines were increased about 4-fold; concomitantly receptor density and cyclic AMP production increased 55% and 65%, respectively. One hour after exercise beta-adrenoceptor density and plasma catecholamines had reached values, which were not significantly different from pre-exercise values, while cyclic AMP production was significantly diminished. It is concluded, that acute increases in concentrations of catecholamines in plasma may increase beta-adrenoceptor density and - responsiveness in human lymphocytes.
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002395:Catecholamines / Q000097:blood; D000242:Cyclic AMP / Q000378:metabolism; D006801:Humans; D020120:Iodocyanopindolol; D007545:Isoproterenol / Q000494:pharmacology; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D005082:Physical Exertion; D010869:Pindolol / Q000031:analogs & derivatives; D011943:Receptors, Adrenergic, beta / Q000502:physiology*
chemical_list: D002395:Catecholamines; D011943:Receptors, Adrenergic, beta; D020120:Iodocyanopindolol; D010869:Pindolol; D000242:Cyclic AMP; D007545:Isoproterenol