Two-color flow cytometry and real-time PCR also revealed that treatment with NPY dose-dependently inhibited M1 macrophage activation by reducing 50% F4/80+iNOS+ cells and largely suppressed expression of proinflammatory cytokines including IL-1β, IL-6 and TNFα in the AKI kidney (Figure 4f, g). This evidence concerns the gene IL6 and acute kidney injury.