To observe the effect of electro-acupuncture for simultaneous regulation of the brain and heart on the behaviors and serum content of atrial natriuretic peptide(ANP)，coticotropin-releasing hormone(CRH)，and corticosterone(CORT) of anxiety model rats and explore the anti-anxiety mechanism.Methods:Thirty-two healthy male SD rats were randomized into normal，model，electro-acupuncture，and sham acupuncture group，with 8 in each group，and chronic unpredictable stress was used to induce anxiety in rats.After 15 days，the elevated plus maze test and open field test were carried out to observe the behavioral changes of rats with anxiety，and the serum levels of ANP，CRH，and CORT were detected by enzyme-linked immunosorbent assay(ELISA).Results:The percentage of times of entering the open arms(OE%) and percentage of time on open arms(OT%) in the elevated plus maze test were decreased(P<0.01)，and the number of squares crossed and the number of rearings in the open field test were reduced(P<0.05) in the model group as compared with those in the normal group.Moreover，the serum levels of ANP，CRH，and CORT in the model group were higher than those in the normal group(P<0.01).OE% and OT% were raised(P<0.01) and the number of squares crossed and the number of rearings were increased(P<0.05) in electro-acupuncture group compared with those in the model group.The serum levels of ANP，CRH，and CORT in the electro-acupuncture group were lower than those in model group(P<0.01).Conclusion:Abnormal levels of ANP，CRH，and CORT in serum may be the cause of anxiety in rats.The electro-acupuncture for simultaneous regulation of the brain and heart might exert the therapeutic effect on anxiety by modulating the levels of the three.