Objective To observe the effect of electroacupuncture(EA)therapy on levels of oxygen free radicals(OFR)and hippocampal apoptosis-related protein expression in ischemic learning-memory disorder rats so as to investigate its mechanisms underlying improvement of ischemic learning-memory impairment.Methods A total of 60 SD rats were randomly divided into sham operation(sham)

model

medication

and EA groups

with 15 rats in each group.The learning-memory disorder model was made by occlusion of bilateral carotid arteries.EA(2-3Hz

2mA)was applied to"Zhi San Zhen"["Shenting"(GV 24)and bilateral"Benshen"(GB 13)]for 30 min

once a day for 3weeks.The rats of the medication group were treated by lavage of Aricept(0.03mg·kg-1·d-1)

once daily for 3weeks.The rats' learning-memory ability was detected by Morris water maze tests and the state of hippocampal apoptosis cells was observed by light microscope after TUNEL staining and the expression of hippocampal Bcl-2

Bax and Caspase-3proteins was detected by immunohistochemistry.Serum and hippocampal superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)activity and malondialdehyde(MDA)contents were detected by chemical colorimetric analysis.Results Compared with the sham group

the escape latencies(place-navigation)after modeling were evidently prolonged

and the times of target-platform crossing in 90sec(spatial probe test)considerably reduced in the model group(P<0.01)

suggesting an impairment of learning-memory ability.After the treatment for 21 d

the increased escape latency and the reduced target-platform crossing time in both EA and medication groups were reversed in comparison with the model group(P<0.01)

suggesting an improvement of memory ability

and the effect of the EA group was significantly superior to that of the medication group(P<0.05).Compared with the sham group

the number of apoptotic cells in hippocampal CA 1-CA 3regions

and the expression levels of hippocampal Bcl-2

Bax and Caspase-3proteins

and serum and hippocampal MDA contents were significantly increased in the model group(P<0.01)

while serum and hippocampal SOD and GSH-Px levels obviously decreased in the model group(P<0.01).After the treatment for 21 days

compared to the model group

the number of the apoptotic cells

the expression levels of hippocampal Bax and Caspase-3proteins

and the contents of serum and hippocampal MDA were notably decreased in the EA and medication groups(P<0.01)

whereas

Bcl-2protein expression levels

and serum and hippocampal SOD and GSH-Px activity were notably up-regulated in the EA and medication groups(P<0.01).The effects of EA group were obviously superior to those of medication group in increasing hippocampal Bcl-2immunoactivity

serum SOD and GSH-Px and hippocampal GSH-Px activity and in down-regulating serum MDA level(P<0.01

P<0.05).Conclusion Electroacupuncture intervention can improve learning-memory ability in ischemic learning-memory disorder rats which may be associated with its effects in reducing blood and hippocampal OFR contents and hippocampal cellular apoptosis.