Fig. 1. Changes over time in serum uric acid concentration (top ) and urinary excretion of uric acid (bottom ) in the four groups. Individual (open symbols) and mean ± SD values (closed symbols) are shown. Serum uric acid concentrations in the groups that received probenecid (low-flow sevoflurane plus probenecid [LSP], high-flow sevoflurane plus probenecid [HSP]) were significantly lower than in the control groups (low-flow sevoflurane [LS], high-flow sevoflurane [HS]) on day 1 after anesthesia. Urinary excretions of uric acid in the probenecid-treated groups were significantly higher than in the control groups during anesthesia. * P < 0.05 compared with each preoperative value. ** P < 0.01 compared with each preoperative value. †P < 0.05, ††P < 0.01 compared with the LS group. @ P < 0.05, @@ P < 0.01 compared with the HS group.