Objective To observe the effect of scalp cluster-needle intervention on cognitive ability and hippocampal vascular endothelial growth factor(VEGF) expression in cerebral ischemia(CI) rats.Methods Forty Wistar rats were rando-mized into sham operation(sham)

model

scalp-acupuncture and medication groups.Chronic CI model was established by occlusion of the bilateral common carotid arteries.Acupuncture needles were inserted into "Baihui"(GV 20) and its left and right points(2 mm beside GV 20) and manipulated leftward and rightward for 3 min at a frequency of about 200 times/min

retained for 30 min.The treatment was conducted once daily

for 4 weeks.For rats of the medication group

Nimodipine(1 mg/kg) was gi-ven to the animal by gavage

once a day

for 4 weeks.The rats' learning ability was measured by Morris water maze.Changes of hip-pocampal cellular morphology were observed by HE staining and light microscope

and hippocampal VEGF expression was detected by immunohistochemistry.Results In comparison with the sham group

the escape latency of rats in the model group was prolonged significantly(P<0.05)

suggesting a decrease of learning ability after CI.Compared with the model group

the escape latency of both acupuncture and medication groups were reduced markedly after the treatment(P<0.05).In comparison with the sham group

the number of VEGF immunoreaction(IR) positive cells in the model group was up-regulated significantly(P<0.05)

while compared with the model group

the numbers of both acupuncture and medication groups were increased further(P<0.05).No significant differences were found between the acupuncture and medication groups in escape latency and VEGF expression levels(P>0.05).HE staining showed that in the model group the hippocampal pyramidal cells were reduced in number

became vaguer in layers and nucleole

and got deformed in structure with karyopycnosis and disappearance of endochylema

and cavitation.These situations were relatively lighter in both acupuncture and medication groups.Conclusion Scalp acupuncture intervention can significantly improve CI rats' congnitive ability and pathological changes

which may be related to its function in increasing the expression of VEGF in the hippocampus.