The effect of one-month amlodipine treatment on plasma endothelin-1 concentration in hypertensive patients

Background Endothelium and smooth muscle protection after calcium antagonists (Ca-A) are markedly related to several mechanisms, among which the influence on endothelin- 1 (a substance regarded as the most powerful endogenous vasoconstrictor) seem to be very important. The aim of this study was to investigate the influence of amlodipine (dihydropyridine Ca-A, III generation) on plasma endothelin-1 (ET-1) and serum aldosterone (Ald) concentration in patients with essential arterial hypertension (EH). Material and methods The study population included 39 patients (18 women and 21 men) with EH in stage I according to WHO classification. Selection criteria excluded patients with a secondary form of arterial hypertension and any additional diseases influencing ET-1 plasma concentration. In all of the patients the following parameters were assessed: — SBP — systolic blood pressure; — DBP — diastolic blood pressure; — ET-1 — endothelin-1 plasma concentration; — Ald — aldosterone serum concentration; before (I study) and after 30-day treatment with amlodipine in dose 5 mg/day (II study). Results 30-day treatment with amlodipine (5 mg/day) led to: 1. Significant decrease of SBP (Mean ± SD: I study: 160.17 ± 9.76 vs II study: 131.78 ± 11.83 mm Hg, p = 0.0000001). 2. Significant decrease of DBP (Mean ± SD: I study: 93.58 ± 7.71 vs II study: 74.17 ± 10.03 mm Hg, p = 0.0000001). 3. Non-significant decrease of ET-1 conc. (Median ± S I study: 83.3 ± 23.9 vs II study: 78.7 ± 20.85 pg/ml, p = = 0.102). 4. Non-significant increase of Ald conc. (Median ± S I study: 125.9 ± 66.53 vs II study: 158.49 ± 76.15 pg/ml, p = 0.52). Conclusion 30-day treatment of essential hypertensive patients with amlodipine in dose 5 mg/day induced a nonsignificant decrease of ET-1 concentration, which may be important for the therapeutic use of amlodipine in everyday practice. However, it should be also noted that our data were collected from a relatively small group of patients (39), and probably need to be confirmed in larger population sample. Arterial Hypertension 2011, vol. 15, no 1, pages 5–12