| PartⅠ Effects of sevoflurane inhalation anesthesia on hyperalgesia in sleep deprived rats Objective: The objective of current study is to investigate whether sevoflurane inhalation anesthesia aggravates the hyperalgesia effect of acute REM sleep deprivation rats.Methods: Experimental animals: 76 male SD rats,aged 10 months,weighing about300 g,were randomly divided into four groups(n=19): sleep deprivation group(SD group): the rats were taken 96-hours acute REM-sleep deprivation in sleep deprivation cages;Sevoflurane inhalation anesthesia group(SEV group): the rats were placed into a platform next to the SD group without sleep deprivation cage for 96 hours,and then given 2.5% sevoflurane for 3 hours.Sleep deprivation + sevoflurane inhalation anesthesia group(SD+SEV group): the rats were given 96 hours sleep deprivation.Another 2.5% sevoflurane was inhaled for 3 hours.Normal Control group(Control group): the rats were placed in a platform beside the SD group without sleep deprivation cage,and no other treatment was conducted.The MWT tests were performed before sleep deprivation(T0),and at 1d,3d and 7d(T1-3)after sevoflurane inhalation,and the time of awakening were measured at the same time.Results:1.Compared with group Control,MWT decreased in SD group and in SEV group at T0-3(P<0.05).2.Compared with SD group,MWT decreased in SD+SEV group at T0-3(P<0.05);3.Compared with other groups,MWT in SD+SEV group decreased progressively at T1-T3(P<0.05),and the recovery time of MWT was longer than that before(P<0.05),while there was no significant difference in postoperative wake time(P﹥0.05).Conclusion: Sevoflurane inhalation anesthesia after acute REM sleep deprivation can trigger hyperalgesia and prolong the recovery time.PartⅡ The regulation of the suprachiasmatic nucleus Egr gene signal pathway in perioperative hyperalgesia Objective: The purpose of this part was to explore whether sevoflurane inhalation anesthesia can aggravate hyperalgesia in acute REM sleep deprivation rats through Egr gene signal pathway.Methods: 72 male SD rats,aged 10 months,were randomly divided into four groups(n=18): sleep deprivation group(SD group): the rats were trained with 96 hours acute REM-sleep deprivation;Sevoflurane inhalation anesthesia group(SEV group): the rats were first placed into a platform next to the SD group without sleep deprivation cage,and then given 2.5% sevoflurane for 3hours.Sleep deprivation + sevoflurane inhalation anesthesia group(SD+SEV group): the rats were given 96 hours sleep deprivation.Another 2.5% sevoflurane was inhaled for 3hours.Normal Control group(Control group): the rats were placed in a platform beside the SD group without sleep deprivation cage,and no other treatment was conducted.The rats were sacrificed at 1d,3 d and 7 d(T1-3).The expression levels of Egr-1 and Egr-2 in the suprachiasmatic nucleus were analyzed by western blot.Serum IL-2,Egr-1 and Egr-2 concentration were detected by ELISA.Spinal cord were immunohistochemical staining to detect IL-2.Results:1.Compared with Control group,the expressions of Egr-1 and Egr-2 in the suprachiasmatic nucleus at T1-3 were up-regulated in the SD group and SD+SEV group.Egr-1 expression was up-regulated in the suprachiasmatic nucleus at T1-3 in SEV group,and Egr-2 expression was up-regulated at T1(P<0.05).Compared with the SD group,the expression of Egr-1 and Egr-2 in the SD+SEV group was up-regulated at T1-3(P<0.05),and the expression of Egr-1 and Egr-2 in the SD+SEV group was up-regulated at T1-3(P<0.05).2.Compared with group Control,serum Egr-1,Egr-2 and IL-2 were increased in the SD group(P<0.05),SEV group(P<0.05)and SD+SEV group(P<0.05).Compared with the SD group,serum Egr-1,Egr-2 and IL-2 were increased in the SD+SEV group(P<0.05);Compared with the SEV group,and serum Egr-1,Egr-2 and IL-2 were increased in the SD+SEV group(P<0.05).Compared with T1,serum Egr-2 expression in SD group decreased with time extension(P<0.05).Compared with T1,serum Egr-2 expression decreased with time extension in SEV group(P<0.05).3.Compared with group Control,integral optical density(IOD)of spinal IL-2 positive cells was increased at T1-3 in SD group(P<0.05)and SEV group (P<0.05).Compared with the SD group,IOD of spinal IL-2 positive cells was increased at T1-3 in the SD+SEV group(P<0.05),and increased at T1-3 in the SD+SEV group(P<0.05).Conclusion: Sevoflurane anesthesia after acute REM sleep deprivation may induce hyperalgesia through the Egr/ IL-2 signaling pathway. |
