ABSTRACT
Animal experiments suggest that an important component of the antihypertensive effects of ACE inhibitors might derive from an inhibition of the sympathetic vasomotor tone. We addressed this problem on 22 mildly hypertensive subjects (48 +/- 2 years; arterial pressure 151 +/- 3/95 +/- 1 mmHg), in whom sympathetic vasomotor tone was non invasively inferred by the power of the low frequency component (0.1 Hz) of the spontaneous oscillations of systolic arterial pressure (LFSAP), during placebo and after 4 weeks of treatment with a new ACE inhibitor, cilazapril, 5 mg per os oid. LFSAP was computed at rest and during physical (active orthostatism) and mental (computerized attentional test and mental arithmetic) stimuli capable of enhancing sympathetic drive. Cilazapril treatment reduced resting arterial pressure to 128 +/- 3/80 +/- 2 mmHg, without affecting heart rate (78 +/- 2 and 74 +/- 2 b/min, respectively). The increases in LFSAP produced by standing were significantly greater during placebo than during active treatment (delta LFSAP = 10 +/- 3 and 5 +/- 2 mmHg2, respectively). These data suggest that an important reduction of sympathetic vasomotor tone accompanies the antihypertensive effects of chronic ACE-inhibitor treatment.
Subject(s)
Blood Pressure/drug effects , Cilazapril/pharmacology , Muscle Tonus/drug effects , Sympathetic Nervous System/drug effects , Vasomotor System/drug effects , Chronic Disease , Cilazapril/therapeutic use , Drug Evaluation , Electrocardiography/drug effects , Electrocardiography/methods , Electrocardiography/statistics & numerical data , Female , Humans , Hypertension/drug therapy , Hypertension/physiopathology , Male , Middle Aged , Signal Processing, Computer-Assisted , Sympathetic Nervous System/physiopathology , Vasomotor System/physiopathologyABSTRACT
The study of hemodynamic and humoral changes stressed the possibility--statistically significant for the values of end diastolic volume (EDV), ejection fraction (EF), end systolic volume (ESV), dopamine (DA), norepinephrine (NE)-to point out the differences between normotensive and hypertensive subjects in the pre-clinic stage during exercise test, and to predict their evolution along with the relative diagnostic, therapeutic and prognostic corollaries.