Effect of antihypertensive treatment with doxazosin on insulin sensitivity and fibrinolytic parameters

The effects of the selective alpha-1-adrenoceptor antagonist doxazosin on metabolic and fibrinolytic parameters were studied in hypertensive patients with various degrees of fasting plasma insulin levels (Group A: 22.5 +/- 3 microU/ml, Group B: 8.1 +/- 1.5 microU/ml; p <0.01) to disclose a potential link between a doxazosin-induced alteration of insulin and/or lipid metabolism and possible changes of these parameters on the fibrinolytic system. Doxazosin treatment resulted in a dose-dependent reduction of basal insulin levels in group A to 16 +/- 3 microU/ml; p <0.05. This finding was paralleled by a dose-dependent increase in t-PAmass concentration in the same patient group (basal t-PAmass from 9.7 +/- 1 to 15.5 +/- 2 ng/ml; p <0.05). As PAI-1 "active" as well as total antigen levels were not altered in parallel, the net effect on the endogenous fibrinolytic system is an increase of the fibrinolytic potential.