Objective To observe the effect of electroacupuncture(EA)on the spatial learning-memory ability and the expression of NR 2Bsubunit of NMDA receptor in the amygdala(AMG)in rats with morphine withdrawal.Methods A total of40 SD rats were randomized into control

model

manual acupuncture and EA groups(n=10in each group).The morphine withdrawal model was established by subcutaneous injection of morphine hydrochloride injection at doses of 20

30

40

50and50mg·kg-1·d-1 continuously for 5days

followed by injection of naloxone(i.p.

3mg/kg)for rapid induction of withdrawal syndrome.Manual acupuncture or EA stimulation was applied to bilateral"Shenshu"(BL 23)and "Zusanli"(ST 36)

once daily for 6days.Morris water maze swimming test was conducted for detecting the rats' spatial learning-memory ability.The expression levels of NR 2Bprotein and mRNA in AMG was measured by Western blot and Real time-PCR

respectively.ResultsCompared to the control group

the escape latency on day 5of swimming tests was obviously prolonged in the model group(P<0.01)

while in comparison with the model group

the escape latencies in both manual acupuncture and EA groups were obviously shortened(P<0.01)

suggesting an improvement of the rats' learning-memory ability.In addition

the expression levels of NR 2Bprotein in both manual acupuncture and EA groups and that of NR 2BmRNA in the EA group were significantly higher than those of the model group(P<0.01

P<0.05).Conclusion Both manual acupuncture and EA interventions can improve the learning-memory ability in morphine withdrawal rats

which is probably partially related to their effects in up-regulating the expression of NR 2Bin the AMG.