Objective      To determine the effects of sevoflurane preconditioning on inflammatory response and myocardial injury in the patients undergoing valve replacement under cardiopulmonary bypassing (CPB) and investigate its underlying mechanisms.       Methods      Twenty-four patients scheduled for elective valve replacement in our hospital from May to August 2015 were recruited in this study

and they were randomly divided into 2 groups (n=12)

sevoflurane preconditioning group and total intravenous anaesthesia group (control). Sevoflurane of 1 minimum alveolar concentration (MAC) was administered for 20 min after intubation followed by a 10 min washout before CPB in sevoflurane preconditioning group

and such administration for the intravenous anesthesia control group. Blood samples were collected for detection of plasma concentrations of TNF-α and IL-6 by ELISA

that of cTnⅠby bidirectional lateral flow immunoassay

and activity of creatine-MB by immunosuppressiom assay after anesthesia induction (T0)

at 2 (T1)

6 (T2)

24 (T3) and 48 h (T4) after aorta de-clamping respectively. A biopsy of the atrium was taken between the end of washout period and start of the CPB to determine the expression of phosphorylated GSK3β and STAT5A by Western blotting.       Results      The plasma concentration of cTnⅠ

TNF-α

IL-6 and the activity of creatine-MB at T1~T3 were significantly increased in both groups when compared with T0 (P0.05). Compared with control group

the concentrations of TNF-α at T1~T2 and IL-6 at T1~T3 were obviously decreased (P0.05)

while the concentration of cTnⅠ and the activity of CK-MB had no differences. The expression levels of phosphorylated GSK3β and STAT5A were significantly increased in the preconditioning group than the control group (P=0.0469

P=0.0058).       Conclusion       Sevoflurane preconditioning reduces the inflammatory reaction in the patients undergoing valve replacement

and exerts cardio-protective effects by enhancing phosphorylation of GSK3β and STAT5A.