To observe the effect of electro-acupuncture for synchronous cardiac and cerebral regulation on the behavior and brain-derived neurotrophic factor(BDNF)-tropomyosin-related kinase B(TrkB) signaling pathway in the rat model of anxiety，and to explore the mechanism of the anxiolytic effect of acupuncture.Methods:Thirty-two SD rats were randomly assigned into a normal group，a model group，an electro-acupuncture group，and a sham acupuncture group(n=8)，and the rat model of anxiety was established with chronic unpredictable stress.The electro-acupuncture was performed at Baihui(GV20)，Fengfu(GV16)，Shenmen(HT7)，Neiguan(PC6)，while the sham acupuncture referred to shallow needling 1 mm beside the above acupoints，once every other day，20 min each time.The model establishment and treatment lasted for a total of 15 days.The elevated plus maze test and open field test were carried out to observe the behavioral changes of rats with anxiety.The level of BDNF in the serum was determined by enzyme-linked immunosorbent assay(ELISA)，and the expression levels of BDNF and TrkB in the prefrontal lobe by immunohistochemical method.Results:Compared with the normal group，the modeling of anxiety decreased the open-arms entries(OE%) and open-arms time(OT%)(P<0.01，P<0.05).In comparison with the model group，electro-acupuncture increased OE% and OT%(P<0.01).Compared with the electro-acupuncture group，sham acupuncture decreased OT%(P<0.05) and tended to decrease OE%(P>0.05).Compared with the normal group，the modeling decreased the number of crossing and rearing(P<0.05，P<0.01).In comparison with the model group，electro-acupuncture increased the number of crossing and rearing(P<0.01).Compared with the electro-acupuncture group，the sham acupuncture decreased the number of crossing and rearing(P<0.05).Compared with the normal group，the modeling lowered the level of BDNF in the serum(P<0.01).In comparison with the model group，electro-acupuncture elevated the level of BDNF(P<0.05).The level of BDNF in the sham acupuncture group was lower than that in the electro-acupuncture group(P<0.05).The expression levels of BDNF and TrkB in the prefrontal lobe in the model group were significant lower than those in the normal group(P<0.01)，while electro-acupuncture up-regulated the expression levels of BDNF and TrkB compared with the model group(P<0.01，P<0.05).In comparison with the electro-acupuncture group，sham acupuncture down-regulated the expression of BDNF and TrkB in the prefrontal lobe(P<0.05).Conclusion:Abnormal expression of BDNF-TrkB signaling pathway may be one of the mechanisms leading to the occurrence of anxiety in rats.Electro-acupuncture for synchronous cardiac and cerebral regulation may help recover the BDNF-TrkB signaling pathway to exert the effect against anxiety.