Nadolol prevents the exercise-induced rise in lymphocyte beta-receptor number in borderline hypertension.
Thirteen borderline hypertensives were investigated at rest and during dynamic exercise, before and after therapy with nadolol (40-80 mg/day for 7-28 days), in order to evaluate regulation of the number of lymphocyte beta-receptors. Systolic blood pressure and the heart rate were measured before and after 15 min of bicycle exercise, both with and without nadolol therapy; blood samples were withdrawn for adrenaline, noradrenaline and lymphocyte beta-receptor determinations. Nadolol induced a significant decrease in systolic blood pressure and the heart rate at rest, while plasma catecholamines and lymphocyte beta-receptors did not change significantly. Of the physiological responses to dynamic exercise (increases in systolic blood pressure, heart rate, plasma noradrenaline levels and adrenaline and lymphocyte beta-receptors), only the rise in beta-receptors was entirely prevented, and the increase in the heart rate was significantly attenuated by nadolol. It is suggested that the lack of a rise in the number of beta-receptors during exercise may contribute to the blunted exercise-induced tachycardia in patients taking nadolol.
Terzoli
L
L
Istituto di Clinica Medica Generale e Terapia Medica, Università di Milano, Italy.
Bragato
R
R
Bolla
G B
GB
Leonetti
G
G
Zanchetti
A
A
D000328:Adult; D004341:Drug Evaluation; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy*; D008214:Lymphocytes / Q000032:analysis / Q000187:drug effects*; D008875:Middle Aged; D009248:Nadolol / Q000627:therapeutic use*; D005082:Physical Exertion / Q000187:drug effects* / Q000502:physiology; D011869:Radioligand Assay; D011943:Receptors, Adrenergic, beta / Q000032:analysis / Q000187:drug effects*
D011943:Receptors, Adrenergic, beta; D009248:Nadolol