Objective To observe the effect of electroacupuncture(EA)of acupoint recipe for "dredging Governor-Meridian

regulating vitality and strengthening the kidney" on learning-memory ability and pathological changes of cerebral minute blood vessels and hippocampal structure in hypertension-hyperlipmia-vascular dementia(HH-VD)rats.Methods Forty SD rats were randomly divided into sham-operation(sham)group(n=8)

EA-Ⅰ group [n=8

EA of "Baihui"(GV 20)

"Dazhui"(GV 14)

"Pishu"(BL 20)and "Shenshu"(BL 23)

80 Hz

1 mA

20 min/day

15 days]

EA-Ⅱ group(n=8

EA of non-points

5 mm lateral to the abovementioned acupoints)

medication group(n=8

intragastric perfusion of Nimotong

0.6 mg/mL

20 mL/kg

15 days)

model group(n=8).HH-VD model was established by feeding the rat with high fat forage and by occlusion of the left renal artery and carotid artery.The animals' learning-memory ability was detected by Y-maze test

the synaptic structure of the hippocampal CA 1 region

and the pathological change of the cerebral cortex were observed by electronic microscope and light microscope

respectively.Results After modeling

the blood pressure

serum total cholesterol and triglyceride(TG)levels

and the error number(EN)

total reaction time(TRT)and standard number(SN

number of paw-electric-stroke for reaching correct reactions)of Y maze test increased significantly in comparison with sham group(P<0.05).After EA

the EN

TRT and SN of EA-Ⅰ

EA-Ⅱ and medication groups decreased significantly in comparison with model group(P<0.01)

suggesting a striking improvement of the learning-memory ability after the treatment

and the EN

TRT and SN of EA-Ⅰ group and medication group were significantly lower than those of EA-Ⅱ group(P<0.05).Under electronic microscope

the number of synapses in hippocampal CA 1 area of HH-VD model rats reduced obviously

its postsynaptic density(PSD)was lighter

and the synaptic vesicles were fewer.Whereas in comparison with EA-Ⅱ and medication groups

the synaptic number and density in EA-Ⅰ group were more and bigger

and the width

length and color of PSD increased clearly.The synaptic number of EA-Ⅱ group was relatively smaller compared with the other two treatment groups.Under light microscope

the vascular walls of the cerebral minute and small arteries of model group were obviously thickened and their lumina narrowed.While in EA-Ⅰ group

these pathological changes were mild.In medication group the thickening of vascular walls of partial cerebral minute and small arteries were also seen.Conclusion EA of acupoint recipe for "dredging Governor-Meridian

regulating vitality and strengthening the kidney" can improve pathological changes of the synaptic structure of hippocampal CA 1 region and the vascular walls of cerebral minute and small arteries

which may contribute to its function in improving the learning-memory ability in HH-VD rats.