Background & objectives: Secretory phospholipase [A.sub.2] (sPL[A.sub.2]) and oxidized low density lipoprotein (oxLDL) are considered as oxidative and inflammatory markers. The effects of oxLDL have been shown to be inhibited by paraoxonase (PON1). This study was undertaken to investigate the relationship between oxidative and inflammatory markers in hypertensive patients with or without antihypertensive drug treatment. Methods: Newly diagnosed hypertensive patients (n=35) and hypertensive patients who had been taking angiotensin converting enzyme (ACE) inhibitors as antihypertensive therapy (10 or 20 mg/day for 9 [+ or -] 2 wk; n=35) and age-matched normotensive subjects (controls; n=20) were included in this study. Plasma sPL[A.sub.2], oxLDL and PON1 activities were determined.