A New Ca-Antagonist, Azelnidipine, Reduced Blood Pressure During Exercise Without Augmentation of Sympathetic Nervous System in Essential Hypertension: A Randomized, Double-Blind, Placebo-Controlled Trial

This study was carried out to evaluate the effect of a new long-acting calcium-channel antagonist, azelnidipine, on hemodynamic and neural responses to exercise. Ten patients (age, 36-69 years) with mild essential hypertension were enrolled in this study. A randomized, double-blind, crossover treatment of azelnidipine at a dose of 8.0 mg once daily for 4 weeks was performed. After a 4-week placebo period, the patients exercised in a submaximal test by using an ergometer with azelnidipine or placebo treatment. The changes caused by exercise in arterial blood pressure (BP), heart rate, cardiac output (CO), and systemic vascular resistance were evaluated. In addition, the plasma norepinephrine (NE), epinephrine (E), plasma renin activity, and plasma aldosterone concentration were determined at rest, at peak exercise, and at the recovery period. Both the SBP and diastolic (D) BP were decreased at rest by azelnidipine treatment (from 158 +/- 10/97 +/- 7 to 145 +/- 14/90 +/- 9 mm Hg). Azelnidipine significantly decreased both SBP and DBP during exercise (SBP, F = 6.09, p < 0.05, Fi = 0.612, NS; DBP, F = 17.78, p < 0.001, Fi = 0.298, NS). No significant changes in the resting heart rate and CO were observed, and the exercise-induced increase of these parameters was also not affected by azelnidipine. Azelnidipine produced no significant change of the resting plasma NE and E levels and an exercise-induced increase of plasma NE. In conclusion, these results indicate that azelnidipine, different from another dihydropyridine-type calcium channel antagonists, does not produce any changes in the hemodynamic and neurohumoral response to exercise, and it may be beneficial for patients with mild essential hypertension.