AMLODIPINE IN AMBULATORY HYPERTENSIVE PATIENTS - HUMORAL AND HEMODYNAMIC-EFFECTS

In order to evaluate the mid-term effects of amlodipine, a 1,4-dihydro pyridine calcium antagonist, as well as its effects on the renin-angio tensin-aldosterone system (RAAS), on water and electrolyte balance, on urinary excretion of albumin (UAE) and on lipid metabolism, thirteen hypertensive patients (2 M, 11 F, mean age 54 years) were studied in t he course of 24 weeks of therapy with amlodipine at 5-10 mg/day. Pre-t herapy and periodically during therapy, the systolic blood pressure (S BP), diastolic blood pressure (DBP) and heart rate (HR) were recorded in the sitting orthostatic positions (2 measurements). Laboratory test s were performed at times 0 and at 24 wks with the patients fasting fo r at least 12 h in the recumbent position. The tests included: plasma renin activity (PRA), plasma aldosterone (PA), serum angiotensin conve rting enzyme (SACE), blood urea nitrogen (BUN), blood creatinine, plas ma electrolytes (Na, K, Cl), triglycerides, total cholesterol (TC) and HDL-cholesterol (HDLC), along with 24-h urine samples (with sterile u rine) to determine UAE. The results of this study demonstrate that SBP , DBP and HR were significantly reduced during the 24 wks of therapy. The water and electrolyte and renal function were not modified. After treatment the levels of TC were significantly reduced. No change was o bserved in the RAAS, while the mean levels of UAE were reduced though not significantly. In conclusion, amlodipine was shown to be effective for the therapy of hypertension; it does not cause reflex tachycardia even in mid-term therapy and was effective in reducing TC levels.