Effect of prazosin treatment on HDL kinetics in patients with hypertension

The effect of prazosin treatment on blood pressure, plasma HDL-cholesterol concentration, and apoprotein-AI/HDL (apoAI/HDL) kinetics was studied in 11 patients with mild hypertension. Blood pressure (mean ± SEM) fell from 143 ± 1/96 ± 1 to 134 ± 1/86 ± 1 mm Hg after 4 to 5 months of prazosin treatment (P < .001), associated with an increase in plasma HDL-cholesterol concentration from 38 ± 2 to 46 ± 2 mg/dL (P < .001). Both the fractional catabolic rate (FCR) and total synthetic rate of apoAI/HDL, which were higher than previous reported values for normal individuals, decreased from 0.36 ± 0.02 to 0.30 ± 0.02 L/day and 17.4 ± 1.1 to 13.8 ± 1.1 mg/kg/min, respectively. These changes were statistically significant, and the post-treatment values for both variables were now within the normal range. When the decay curve was further analyzed by nonlinear curve fitting, it was shown that the return to normal of the FCR of apoAI/HDL in patients treated with prazosin was accounted for by the decrease of the decay constants of the second [p(2)] and third [p(3)] components of the ¹²⁵I-AI/HDL disappearance curve. In conclusion, abnormalities in HDL concentration and HDL kinetics exist in patients with very mild hypertension. These defects were significantly improved with prazosin treatment, and this may render the compound of particular clinical benefit in the treatment of patients with mild hypertension.