Venous blood was extracted after a 12-h fast, and after 30, 60, 120, and 240 min after consumption of the breakfast. The samples were collected in tubes containing 1 g · l−1 EDTA or 3.8% citrate, and were stored in containers with ice and kept in the dark. A similar procedure was used for the different determinations of the samples in all the other periods, avoiding exposure to air, light, and room temperature. Plasma was obtained by low speed centrifugation at 1,500 × g for 15 min at 4°C within one hour of extraction. Lipid parameters were assessed with the modular autoanalyzer DDPPII Hitachi (Roche, Basel, Switzerland), using specific reagents (Boehringer-Mannheim, Mannheim, Germany). Total cholesterol and TG levels were determined by colorimetric enzymatic methods (15- 16). High-density lipoprotein cholesterol (HDL-C) levels were measured using colorimetric assay after precipitating the lipoproteins containing apolipoprotein B with polyethylene-glycol (17). Low-density lipoprotein cholesterol (LDL-C) levels were estimated using the Friedewald formula based on the CT, TG, and HDL-C values (18). Apolipoprotein Al and apolipoprotein B levels were measured by immunoturbidimetry (19). The chylomicron and large very low-density lipoprotein fraction of large triglyceride-rich lipoproteins (TRL) (Sf > 400) was isolated from 4 ml plasma overlayered with 0.15M NaCl, 1 mM EDTA (pH 7.4; density, 1.006 kg·l−1) by a single ultracentrifugal spin (28,000 × g, 30 min, 4°C) in a 50-type rotor (Beckman Instruments, Fullerton, California). Chylomicrons contained in the top layer were removed by aspiration after cutting the tubes. The infranatant was centrifuged at a density of 1.019 kg·l−1 for 24 h at 115,000 × g in the same rotor. The nonchylomicron fraction of TRL (also referred to as small TRL, Sf 20 to 400) was removed from the top of the tube. All operations were done in subdued light. Large and small TRL fractions were kept at −70°C until TC and TG levels of the same were ready to be analyzed. Using the frozen samples of plasma or serum, we determined the levels of lipoperoxides (LPO) by colorimetric method (LPO-CC Assay, Kamiya Biomedical Company, Seattle, Washington); 8-epi prostaglandin-F2α (8-epi-F2α) by immunoenzymatic assay (Bioxytech 8-isoprostane Assay, Oxis Research, Portland, Oregon); and nitrates/nitrites (NO(x)) by colorimetric method (Nitrate/Nitrite Colorimetric Assay Kit, Cayman Chemical, Ann Arbor, Michigan). All the determinations were carried out in duplicate.