Fig 1: IDO1 expression in the cardiac macrophage cells and the plasma of mice remodeling after MI. (A) Induction of MI by the permanent ligations of the left anterior descending artery (MI) at 1d, 3d, 7d, 14d, and 28d points or sham operations without ligation were performed on the experimental animals as described previously. Immunohistochemical analyses showed that IDO1 and CD68 were co-localized in the infarct and non-infarct area at different time points after MI, indicating that IDO1 was highly expressed in macrophage cells especially during 1−3 days after MI (scale bar, 1000 μm, scale bar, 40 μm). (B) IDO1 expression in heart was determined at different time points after MI using western blot analysis, NS, not significant, *P<0.05 vs sham group, **P<0.01 vs sham group, n=3. (C) IDO1 expression in the infarct and non-infarct area after MI was showed in the western blot analysis, *P<0.05 vs sham group, **P<0.01 vs sham group, n=3. (D) The colocalization of IDO1 with CD68 demonstrated with immunofluorescence in macrophage cells. (E) Distribution of Trp metabolites between the sham and MI group at different time points. Trp, tryptophan; Kyn, kynurenine; 3-HK, 3-hydroxykynurenine; KA, kynurenic acid; XA, xanthurenic acid; 3-HAA, 3-hydroxyanthranilic acid, *P<0.05 vs sham group, **P<0.01 vs sham group, n=3.