Oral glucose tolerance tests (OGTT). After the injection of PPARs inhibitor for two weeks, a glucose solution was administered by intragastric gavage at a dose of 1 g/kg body weight after 6 h fasting. HOMA-IR calculated by the blood glucose levels and the plasma insulin levels at 0 min (A). The blood glucose and plasma insulin concentration were measured at 0, 15, 30, 60 and 120 min after glucose administration (B, C). Glucose area under the curve (G-AUC) and insulin area under the curve (I-AUC) calculated over 30-min periods after oral glucose administration (D, E). G-AUC and I-AUC are represented as the relative levels to those of the B(-) group. Data is shown as mean ± SE (n = 3 - 4). Significance of difference is indicated as different alphabet: p < 0.05.