Objective To observe the effect of electroacupuncture(EA) on the learning-memory ability in Alzheimer's disease(AD) rats.Methods Thirty SD rats were equally randomized into control

model and EA groups.AD model was established by injecting β-amyloid(Aβ25-35

10μg) into the bilateral dentate gyri of the hippocampal CA 1 area(AP-3.5mm

ML±2.0mm

DV 2.7mm).EA(4Hz

1-2mA) was applied to "Baihui"(GV 20)

"Dazhui"(GV 14)

bilateral "Shenshu"(BL 23) and bilateral "Yongquan"(KI 1) for 30min

once daily for 7 days.The learning-memory ability was detected by using step-down test.Long term potentiation(LTP) of hippocampal CA 1 area was recorded by using tungsten microelectrodes after high frequency stimulation(HFS) conditioning of the cortical anterior perforated substance.Results In AD rats

the error number and total error time of step-down test were increased significantly(P<0.05

P<0.01)

and the slope of the excitatory post-synaptic potential(EPSP)

and the amplitude and area of population spikes(PS) at 30min

60min

90min and 120min after high-frequency stimulation of the cortical anterior perforated substance lowered markedly in comparison with sham operation(control) group(P<0.05

P<0.01).After EA treatment

the error number and total error time decreased significantly

the slope of EPSP

and the amplitude and area of PS from 30min to 120min after high-frequency stimulation increased considerably in compa-rison with model group(P<0.05

P<0.01)

suggesting an improvement of the synaptic transmission after EA.Conclusion EA can improve AD rats' learning-memory ability and raise the slope of EPSP and the amplitude of PS

which may contribute to its effect in relieve symptoms of AD in clinic.