Abstract: Objective To investigate the expression of cold-inducible RNA binding protein(CIRP) in the rats hippocampus after cardiopulmonary resuscitation (CPR). The possible role of CIRP in cardiac arrest/cardiopulmonary resuscitation(CA/CPR)-induced brain ischemia/reperfus injury in rats was investigated in this study.Methods 36 adult male Sprague Dawley (SD) rats were randomly divided into two groups using a random number table (n=18): sham group and ischemia-reperfusion 48h(I/R48h) group.Sham group was given tracheal intubation and arteriovenous puncture only and no electrical stimulation was given.I/R 48h group were given tracheal intubation and arteriovenous puncture ,then establishment of cardiac arrest model induced by transesophageal electricalstimulation induced ventricular fibrillation . At 48h after return of spontaneous circulation (ROSC), neurodeficit Score (NDS) was evaluated ;neuronal death was analyzed by hematoxylin and eosin (H&E);microglialactivation was evaluated by detecting the expression of ionized calcium-binding adaptermolecule-1(Iba-1) by immunohistochemistry ;the expression of CIRP in the hippocampus were determined by Western blot.Results The neurological function score was better in sham-operated rats than those that were underwent CA/CPR(P<0.05);the neuronal death were enhanced in the hippocampus CA1 region of three I/R48h group as compared with those in the sham-operated group (P<0.05);microglia were activated theneuronal death was aggravated in the hippocampus CA1 region of mice subjected to I/R48h group as compared with those in t he sham-operated group (P<0.05);the expression level of total protein and cytoplasm protein of CIRP in the hippocampus were significantly increased in the hippocampus in I/R48h group compare to sham group(P<0.05）.Conclusions CA/CPR can induce high expression of CIRP ,CIRP can run from the nucleus to thecytoplasm,cirp may be involved in the early inflammatory reaction process of braintissue damage after CA/CPR in rats