Plasma lipid and lipoprotein changes in hypertensive patients treated with propranolol and prazosin

The effects of propranolol and prazosin on plasma lipoproteins in patients with essential hypertension were evaluated according to a crossover protocol of two 8-week periods with a washout of 4 to 6 weeks. Eleven patients with moderate hypertension (greater than 90 but less than or equal to 144 mm Hg, diastolic) and slightly overweight (+10% to +/- +30%, according to Metropolitan Life Insurance tables) were selected. No dietary changes were prescribed. Plasma cholesterol, triglycerides (TG), and lipoprotein changes were monitored at the beginning of each sequence and at 2-, 4- and 8-week intervals. Prazosin, when given first, did not essentially modify any of the metabolic parameters, except for a slight elevation in plasma apoprotein AI levels, i.e., the main protein component of high density lipoprotein (HDL); propranolol caused a significant rise in total TG and very low density lipoprotein TG (VLDL-TG) levels (+37.3% and +23.9%, respectively). Somewhat lower total TG (+19.6%) and vLDL (17.8%) TG elevations were noted when propranolol was given first; plasma glucose was also significantly raised (+12.8%). Triglyceride and glucose levels returned to normal upon changing to prazosin. Total plasma- and lipoprotein-associated cholesterol levels were essentially unchanged with either drug; similarly, no significant changes were detected in total plasma apoprotein B (the main protein component of LDL and also VLDL), a component of apoprotein AI levels. Uric acid levels were slightly raised on propranolol. There was an 8.8% reduction in uric acid levels when the medication changed from propranolol to prazosin.