Amlodipine increases nitric oxide production in exhaled air during exercise in patients with essential hypertension.
BACKGROUND
Endothelial production of nitric oxide (NO) is attenuated in patients with essential hypertension. We investigated whether treatment with amlodipine increased exhaled NO output (VNO) at rest and during exercise in patients with essential hypertension.


METHODS
We studied the effect of amlodipine in seven untreated hypertensive patients. Cardiopulmonary exercise testing and NO measurement of exhaled air were performed on these patients before and after 2 months of amlodipine treatment.


RESULTS
Amlodipine decreased blood pressure (BP) both at rest and during exercise (at rest: 147.1 +/- 6.4 [SEM]/89.9 +/- 4.4 v 133.6 +/- 5.4/82.7 +/- 3.9 mm Hg, P <.05; at peak exercise: 224.9 +/- 8.0/113.1 +/- 5.3 v 207.0 +/- 6.0/100.7 +/- 5.0 mm Hg, P <.05) without affecting heart rate (at rest: 67.6 +/- 3.9 v 70.4 +/- 4.5 beats/min, P =.33; peak exercise: 146.4 +/- 7.4 v 144.0 +/- 7.2 beats/min, P =.49). Amlodipine did not affect minute ventilation (VE) at rest or during exercise. It did not alter anaerobic threshold, peak oxygen uptake (peak VO(2)), or peak workload. However, after amlodipine treatment, VNO was significantly greater both at rest (130.8 +/- 19.4 v 180.4 +/- 24.8 nL/min, P <.05) and at peak exercise (380.0 +/- 47.5 v 582.6 +/- 74.3 nL/min, P <.05).


CONCLUSIONS
Amlodipine increased NO production, at least in the pulmonary circulation, in patients with essential hypertension. In addition to its antihypertensive effect, the enhancement of NO production by amlodipine in the vasculature of other organs may contribute to its beneficial effects on the cardiovascular system.
Kato
Masayoshi
M
Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan. mkato-tky@umin.ac.jp
Matsumoto
Akihiro
A
Nakajima
Toshiaki
T
Hirose
Ken
K
Iwasawa
Kuniaki
K
Takenaka
Katsu
K
Yamashita
Hiroshi
H
Sugiura
Seiryo
S
Hirata
Yasunobu
Y
Nagai
Ryozo
R
D000328:Adult; D017311:Amlodipine / Q000008:administration & dosage*; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects; D001944:Breath Tests; D015444:Exercise; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*
D000959:Antihypertensive Agents; D017311:Amlodipine; D009569:Nitric Oxide