ABSTRACT
BACKGROUND: Hypertension is a major health problem in both developed and developing countries. It is hypothesized that high blood pressure is associated with loss of balance between peroxidation and antioxidant factors. MATERIAL/METHODS: 40 patients with essential hypertension were studied to ascertain the effects of a selective b1-blocker (acebutolol, 400 mg/day) on serum lipids, antioxidant status, antioxidant enzyme activity in red blood cells (RBC), and membrane fatty acids composition. Each subject was screened by physical examination, ECG, echocardiography, and laboratory tests. The period of observation was 24 weeks, and the data were tested by 2-way ANOVA followed by Bartlett's least significant difference test. RESULTS: At 12 weeks, serum triacylglycerol was more elevated (+26%). At 24 weeks, apolipoprotein A-1 levels remained more elevated (+41%) in hypertensive subjects compared to controls. In hypertensive patients, total antioxidant status and total plasma antioxidant capability were lower at 12 weeks than controls, and increased after 24 weeks of treatment. At 12 weeks, superoxide dismutase, catalase and glutathione reductase activities in erythrocytes remained lower in hypertensive subjects compared to controls (-32%, -40% and -24%, respectively). At 24 weeks, these values were increased compared to those obtained at 12 weeks (+26%, +36% and +37%, respectively). At 12 and 24-weeks, total n-3 and n-6 fatty acids were decreased by 26%, 18% and 29%, 25%, respectively. CONCLUSIONS: These findings demonstrate the beneficial influence of a beta1-blocker (acebutolol) at 24 weeks by its action on serum lipids, antioxidant status and RBC antioxidant enzyme activities.