Effect Of Propofol On Postresuscitation Brain Injury And Endoplasmic Reticulum Stress In A Rat Model Of Cardiac Arrest

Object:To explore the effect of propofol pretreatment on postresuscitation brain protection in a rat model of cardiac arrest and the relationship with endoplasmic reticulum stress(ERS).Methods:Forty-five male SD rats were randomly into sham group(n=15),Intralipid group(n=15)and Propofol group(n=15).Rats of sham group conduct all operations without induce cardiac arrest. Rats of Intralipid group and Propofol group were operated to induce cardiac arrest(6 minutes) by transcutaneous electrical stimulation to epicardium. In Propofol group,propofol(10mg/kg)was administrated via the intraperitoneal 30 min before induce cardiac arrest. In Intralipid group,same volume MCT/LCT was administrated via the intraperitoneal 30 min before induce cardiac arrest. Observing the survival rats at 24 h after restoration of spontaneous circulation(ROSC)and evaluating the neurological state by neurological deficit score(NDS). Then,brains were removed for further research:(1)Observing the histopathological changes in the CA1 region of the hippocampus by hematoxylin-eosin(HE) staining;(2)Observing the apoptosis situation of nerve cell in the CA1 region of the hippocampus by TUNEL assays;(3) Western-blot analysis glucose-regulated protein 78( GRP78)? X-box binding protein 1( XBP-1)? C/EBP homologous protein(CHOP)and caspase12 expression in hippocampus.Results:(1)Compared with the sham group, the rats in Intralipid group and Propofol group have poorer neurological outcomes(P<0.05);Compared with the Intralipid group,there were a significant improvement in NDS in Propofol group(P<0.05);(2)Compared with the sham group, the rats in Intralipid group and Propofol group have varying degrees histopathological changes in the CA1 region of the hippocampus; Compared with the Intralipid group,histopathological changes in the CA1 region of the hippocampus have some alleviate in Propofol group;(3)Compared with the sham group,the rats in Intralipid group and Propofol group have a higher apoptosis index(P<0.01);Compared with the Intralipid group,there were a significant improvement in apoptosis indexin Propofol group(P<0.01);(4)The expressive protein of GRP78?XBP-1?CHOP and caspase12 in Intralipid group and Propofol group were higher than sham group(P<0.01). The Propofol group had lower expressive protein of XBP-1?CHOP and caspase12 than Intralipid group(P<0.01),but higher expression of GRP78 protein(P<0.01).Conclusion:Propofol pretreatment can mitigate brains injury from 24 h after ROSC and the function possibly through the inhibition of ERS.