Nilvadipine protects low-density lipoprotein cholesterol from in vivo oxidation in hypertensive patients with risk factors for atherosclerosis

Objective: Nilvadipine, a calcium antagonist, has been shown to have antiox idant activity in vitro, but its effect on in vivo oxidation has not been a ssessed. The aim of this study was to investigate the antioxidant effect of this agent in vivo. The ratios of 7-keto cholestadien to cholesterol are b elieved to be an available marker of lipid peroxidation. Using these ratios , we have assessed the antioxidant effect of nilvadipine on low-density lip oprotein (LDL) in hypertensive patients with high risk of atherosclerosis. The risk factors of atherosclerosis may involve oxidation of LDL. Methods: Fifteen healthy subjects (seven females and eight males aged 35-72 years, mean +/- SD = 55.3 +/- 13.8 years) and fifteen hypertensive patient s (seven females and eight males aged 45-80 years, mean +/- SD = 60.2 +/- 1 1.8 years) were recruited. Patients were treated orally with nilvadipine (4 mg b.i.d.) for 4 weeks. Cholesterol oxidation levels of LDL in patients be fore and after nilvadipine therapy and healthy subjects were studied. Results: The ratios of 7-keto cholestadien to cholesterol in LDL of hyperte nsive patients before and 4 weeks after nilvadipine treatment and in health y subjects were 6.5 +/- 1.6% (mean +/- SD), 3.8 +/- 1.2%, and 0.2 +/- 0.1%, respectively. There were significantly (P < 0.001) increased levels of cho lesterol oxidation in LDL in patients with hypertension both before and aft er nilvadipine treatment compared with healthy subjects. However, there was a significantly (P < 0.001) decreased level of cholesterol oxidation in LD L in patients after nilvadipine treatment compared with patients before nil vadipine treatment.