Changes in plasma norepinephrine concentration and thrombocyte alpha 2-adrenoceptor density during long-term antihypertensive therapy with nitrendipine and captopril.
Antihypertensive drugs influence the sympathetic nervous system in different ways that may cause adverse or beneficial effects. We treated 48 hypertensive patients with either nitrendipine (10-20 mg twice daily, b.i.d.) or captopril (25-50 mg b.i.d.) for 16 weeks to evaluate changes in plasma catecholamines, platelet alpha 2- and lymphocyte beta 2-adrenoceptors. Blood pressure (BP) decreased from 153/95 to 135/87 mm Hg with captopril and from 155/99 to 137/89 mm Hg with nitrendipine. Treatment with nitrendipine significantly stimulated plasma norepinephrine (NE) from 327 +/- 37 to 446 +/- 50 pg/ml, and treatment with captopril resulted in a significant reduction in platelet alpha 2-adrenoceptor density from 265 +/- 39 to 171 +/- 26 fmol/mg protein. Despite having equal BP-lowering properties, captopril and nitrendipine have different effects on the sympathetic nervous system. Stimulation of plasma NE during long-term treatment with nitrendipine may contribute to possible adverse effects, whereas reduction in alpha 2-adrenoceptors induced by captopril may contribute to the vasodilating effect of angiotensin-converting enzyme (ACE) inhibition.
Müller
R
R
Medical Clinic II, University of Cologne, Germany.
Steffen
H M
HM
Weller
P
P
Kugel
C
C
Freiheit
T
T
Krone
W
W
D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D002216:Captopril / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D004341:Drug Evaluation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009568:Nitrendipine / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D009638:Norepinephrine / Q000097:blood*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000378:metabolism; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism; D016037:Single-Blind Method; D013564:Sympathetic Nervous System / Q000187:drug effects
D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D009568:Nitrendipine; D002216:Captopril; D009638:Norepinephrine