Sleep-wake rhythm after extracorporeal circulation in New Zealand rabbits / 中南大学学报(医学版)

ABSTRACT

Objective:To evaluate the change of sleep-wake rhythm after extracorporeal circulation (ECC) in New Zealand rabbits,and to explore the role of clock genes in sleep-wake rhythm disorder by ECC.Methods:A total of 54 New Zealand rabbits were randomly divided into 3 groupsa normal group (Group N),a sham group (Group S) and a model group (Group ECC).Electrocorticogram (ECOG),electroophthalmogram (EOG) and electromyogram (EMG) were respectively recorded by multipurpose EEG recorder,and the sleep-wake rhythm was also recorded.The mRNA and protein expressions of period1 (Per1) and cryptochrome1 (Cry1) were detected by semiquantitative reverse transcriptase PCR (RT-PCR) and Western blot in pineal gland of rabbits.The differences between the 3 groups were compared.Results:1) Compared with the Group N and Group S at 24,48 h respectively,the total amount of sleep (TAS),light time,slow wave sleep (SWS) in the Group ECC at 24,48 h were significantly reduced (all P＜0.05),and the proportion of light sleep increased (all P＜0.05),the proportion of SWS decreased (all P＜0.05);2) Compared with the Group N and Group S,the expression of Per1 mRNA in the Group ECC at 24,48 h and Cry1 mRNA at 24 h significantly increased (all P＜0.05);3) Compared with the Group N and Group S,the expression of Perl protein in the Group ECC at 48 h and Cry1 protein at 24 h significantly increased (all P＜0.05);4) In the Group ECC,the sleepwake rhythm disorder and clock genes expression were ameliorated at 72 h after surgery.Conclusion:ECC can cause sleep-wake rhythm disorder in New Zealand rabbits,which may be related to the abnormal expression of Per1 and Cry1,and their transcription proteins.