Abstract: Objective To explore the effect of PD98059 on the content of inflammatory cytokines in brain and the vitality of astrocyte after cardiac arrest / cardiopulmonary resuscitation (CA / CPR). Methods Eight rats were selected randomly in 24 healthy SD rats, only subjected to anesthesia and vascular separation without CA induction (Sham group), and the remaining 16 rats were given CA induction by trans-esophageal electrical stimulation after anesthesia. CPR was performed until 6 min later after the induction.The rats that recovered their spontaneous circulation were randomly divided into two groups, receiving the injection with either PD98059 (0.3 mg/kg, PD group, n=8) or normal saline of the same volume (NS group, n=8). After 24 hours, neural function was assessed by neural defect scores (NDS).The expression of p-ERK and GFAP were detected by Western blot assay. The number and vitality of astrocyteon brain slices were assessed by GFAP immunohistochemical staining. The contents of IL-6, IL-1β and TNF - α were measured by relevant ELISA assay kits. Results Compared to the Sham group, NS group showed a significantly decreased NDS, both the expression levels of pERK and GFAP were decreased, and the number and vitality of astrocytes also decreased while the content of inflammation cytokines was increased. Compared to the NS group, the PD group showed a significantly increased NDS, both the expression levels of p-ERK and GFAP were increased, the number and vitality of astrocytes were increased while the content of inflammation cytokines was decreased (P＜0.01). Conclusion PD98059 can down-regulate the levels of inflammatorycytokines IL-6, IL-1β and TNF-α in brain after CA/CPR, and resume the number and vitality of astrocytes in brain.

Key words: heart arrest, cardiopulmonary resuscitation, brain ischemia, reperfusion injury, astrocytes, extracellular signal-regulated MAP kinases, PD98059, inflammation cytokines