Impact of postprandial hypertriglyceridemia on vascular responses in patients with coronary artery disease: effects of ACE inhibitors and fibrates

We analyzed vascular responses (endothelial function, oxidant stress) to po stprandial hypertriglyceridemia (PHTG) in patients with coronary artery dis ease (CAD) to reveal potential therapeutical effects of angiotensin convert ing enzyme inhibition (ACE-I) and of lipid lowering (fibrate). The study po pulation (n = 39, mean age: 60 years) consisted of four groups, all of whic h had angiographically documented CAD. A high fat group (n = 9) consumed a high fat meal, a low fat group (n = 9) a low fat meal, and ACE-I (n = 10) o r fibrate (n = 11) groups consumed a high fat meal plus lisinopril or fenof ibrate. Serum triglycerides (TG) increased significantly 2 h after eating a test meal in all groups with the exception of the low fat group. In the hi gh and low fat groups changes of serum TG were positively correlated (r = 0 .664, P < 0.005) with changes of phorbol ester-activated leukocyte superoxi de anion radical (O-2(-.)) formation and were negatively correlated (r = -0 .488, P < 0.05) with flow-mediated brachial artery dilation (FMD). There wa s a negative correlation (r = -0.419, P = 0.094) between FMD and changes of O-2(-.) formation in the high and low fat groups. In the ACE-I and fibrate groups, O-2(-.) formation decreased 2 h after eating a test meal (from 5.3 4 +/- 1.01 to 3.81 +/- 1.15 nmol/10(6)cells per min, P < 0.01, and from 4.6 6 <plus/minus> 0.91 to 4.26 +/- 0.97 nmol/10(6)cells per min, P = 0.374, re spectively). However, endothelial function did not show any significant cha nges 2 It after eating a test meal in all groups. PHTG increases oxidant st ress and further deteriorates endothelial function, even in patients with C AD. Both ACE-I and fibrates have an antioxidant effect but no acute benefic ial effects in terms of endothelial function under conditions of PHTG in CA D patients. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.