Expression of CD80 and CD206 in F4/80high and CD11bhigh kidney macrophages after heat stress (HS). Using flow cytometry, we analyzed kidney macrophages by focusing on CD80 and CD206 expression in F4/80high or CD11bhigh macrophages. On day 1, the population of CD80-positive F4/80high macrophages (A) and CD11bhigh macrophages (B) was larger in the HS group than in the sham group. In the HS group, the population of CD206-positive F4/80high macrophages (C) and CD11bhigh macrophages (D) on day 7 was higher than that on day 0. On day 1, the ratio of CD80-positive to CD206-positive macrophages (the M1-to-M2 ratio) in the F4/80high (E) and CD11bhigh (F) macrophages were both significantly higher in the HS group than in the sham group, whereas in the HS group, they were significantly lower on day 7 than on day 1. Data represent means ± SE from 8 to 10 mice in each group. *P < 0.05; **P < 0.01.