title: Dynamic exercise-induced increase in lymphocyte beta-2-adrenoceptors: abnormality in essential hypertension and its correction by antihypertensives.
abstract: We compared the effects of acute stimulation of sympathetic activity by dynamic exercise on a bicycle on lymphocyte beta 2-adrenoceptor density and 10 mumol/L (-)-isoprenaline-evoked lymphocyte cyclic adenosine monophosphate increases in normotensive volunteers with those in patients with essential hypertension. In normotensive subjects exercise increased lymphocyte beta 2-adrenoceptors by about 100%. This effect seems to be a beta 2-dependent process, since it is prevented by propranolol (5 mg administered intravenously) and the beta 2-selective antagonist ICI 118,551 (25 mg t.i.d. orally for 2 weeks) but not by the beta 1-selective antagonist bisoprolol (2.5 mg administered intravenously). In patients with essential hypertension who have elevated lymphocyte beta 2-adrenoceptors, dynamic exercise caused only marginal beta 2-adrenoceptor changes, suggesting an impairment of the acute beta-adrenoceptor regulation. Normalization of blood pressure by antihypertensive treatment resulted in a significant fall in lymphocyte beta 2-adrenoceptors and in a restoration of exercise-induced beta 2-adrenoceptor increases. It is concluded that in essential hypertension the impairment of beta-adrenoceptor regulation is directly linked to the elevated blood pressure.
mesh_terms: D000328:Adult; D001794:Blood Pressure; D004837:Epinephrine / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D005082:Physical Exertion; D011433:Propranolol / Q000494:pharmacology* / Q000627:therapeutic use; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*; D012083:Renin / Q000097:blood
chemical_list: D011943:Receptors, Adrenergic, beta; D011433:Propranolol; D012083:Renin; D009638:Norepinephrine; D004837:Epinephrine