The effects of electroacupuncture on the synaptic structure of hippocampal CA3 neurons and learning and memory ability after cerebral infarct

Abstract

Objective To evaluate the effects of electroacupuncture (EA) on synaptic interface structures around a cerebral infarct and evaluate how learning and memory relate to synoptic structure. Methods Forty-eight male, adult Wistar rats were divided randomly and equally into an EA group and a control group after models of ische-mic brain injury had been established. Each group was then divided into 1 week, 2 week and 3 week sub-groups. In the EA group EA was started 24 hours after the operation at the Baihui (DU20) and Da Zhui (BUI4) points and continued for one week, two weeks or three weeks. The control group was fed in normal cages and had no special treatment. Synoptic substructures in the hippocampal CA3 area of the ischemic side were assessed morphologically and quantitatively. Results The synaptic curvatures and postsynaptic density (PSD) an well as the width of the ac-tive area increased significantly in the EA group compared with the control group. Morris water maze learning ability in the EA group exceeded that in the control group. Spatial probe test results also significantly improved in the EA groups compared with the control groups. Conclusions Learning and memory improved in the injured rats following EA, and this is likely to be related to synaptic changes and synaptic plasticity increasing. Key words: Electroacupuncture; Cerebral infarction ; Learning and memory ; Synoptic substructures; Rata