Changes of miR-146a expression in postoperative cognitive dysfunction mice / 临床麻醉学杂志

ABSTRACT

Objective To investigate the changes of miR-146a expression in serum,hippocam-pus and prefrontal cortex in postoperative cognitive dysfunction (POCD) mice.Methods Fifty healthy male C57BL/6 mice,aged 12-14 weeks,weighing 25-30 g,were randomly divided into two groups (n =25 each)using a random number tablecontrol group (group C)and anesthesia plus sur-gery group (group AS).Mice in group AS underwent open tibial fracture of the left hind paw with in-tramedullary fixation in aseptic conditions under general anesthesia with 2.1% isoflurne.Ten mice in each group received the fear conditioning test (FCT)on the 1,3 and 7 days after anesthesia/surgery. The rest of mice were sacrificed 24 h before (baseline),and 6,12,24,48 h after anesthesia/surgery, and then the serum,prefrontal cortex and hippocampus were collected or removed for detection of the expression of miR-146a using quantitative reverse transcription polymerase chain reaction (qRT-PCR).Results Compared with group C,the percentage of freezing time in contextual FCT was sig-nificantly decreased (P <0.05)in group AS,while no significant change in freezing time percentage was found in tone-cued FCT.In serum,compared with group C,miR-146a expression at 6,12,24, 48 h after anesthesia/surgery was significantly up-regulated in group AS (P < 0.05 );and in group AS,the expression of miR-146a was significantly decreased 6,24,48 h as compared to that at 12 h after anesthesia/surgery (P <0.05).In hippocampus,compared with group C,miR-146a expression at 6,12,24,48 h after surgery was significantly up-regulated in group AS (P <0.05);and in group AS,the expression of miR-146a at 6,48 h after surgery was significantly decreased as compared to that at 12 h after anesthesia/surgery (P <0.05).In prefrontal cortex,compared with group C,miR-146a expression at 24,48 h after surgery was significantly up-regulated in group AS (P <0.05);and in group AS,the expression of miR-146a was significantly increased at 48 h as compared to that at 24 h after anesthesia/surgery (P <0.05).Conclusion The expression of miR-146a in serum,hippocam-pus and prefrontal cortex in POCD mice was up-regulated,and changes of miR-146a expression may be related to the development of POCD.