Antihypertensive action of bendroflumethiazide: increased prostacyclin production?

A within-patient randomized, double-blind, crossover study was performed to investigate mechanisms of action of bendroflumethiazide in mild essential hypertension. Significant reductions in lying, standing, and postexercise blood pressure were seen after both 3 days and 10 wk treatment with bendroflumethiazide 10 mg daily. Plasma levels of 6-oxo-PGF1 alpha, the chemical hydrolysis product of prostacyclin, were increased by both 3 days and 10 wk therapy with bendroflumethiazide. This raises the possibility that thiazides may reduce peripheral resistance by increasing prostacyclin biosynthesis.