Impaired flow-mediated vasoactivity during post-prandial phase in young healthy men

Impaired flow-mediated vasodilation in large arteries is an expression of e ndothelial dysfunction and an established marker of early atherosclerosis. Post-prandial lipemia can induce an impairment of the endothelial function. The aim of our study was to evaluate the effects of post-prandial phase on flow-mediated vasodilation in a group of ten young (23+/-2 years) healthy men without cardiovascular risk factors, who underwent an oral fat-loading test. Flow-mediated vasodilation of the brachial artery and serum lipid pro file were assessed under fasting conditions and 2, 4, 6 and 8 h after a hig h-fat meal. Triglycerides increased from 0.6+/-0.2 fasting to 1.1+/-0.5 and 1.3+/-0.6 mmol/l at the 2nd and 4th hour (both P<0.01), and decreased ther eafter. Flow-mediated vasodilation fell significantly from 14.5+/-6.6% fast ing to 3.5+/-1.5% and 4.0+/-2.2% at the 2nd and 4th hour (both P<0.01), and returned to the basal values at the 6th and 8th hour. A strong inverse cor relation was observed between the area under the incremental curve of post- prandial triglycerides (i.e. after subtraction of baseline triglycerides) a nd the area under the decremental curve of post-prandial flow-mediated vaso dilation (r = -0.70, P = 0.025. No association was found between post-prand ial vasodilation changes and fasting triglycerides, other lipid parameters or insulin. We conclude that a transient post-prandial impairment in brachi al artery flow-mediated vasodilation is evident in young healthy men after a high-fat meal, and is closely associated with triglyceride levels. These data provide support for a role of post-prandial phase in vascular regulati on in young healthy subjects. (C) 2000 Elsevier Science Ireland Ltd. All ri ghts reserved.