[Effect of electroacupuncture intervention at different time-points of post-modeling on hippocampal monoamine neurotransmitter levels in mice with vascular dementia].

Objective: To observe the effect of electrocupuncture (EA) intervention at different time-points of post-modeling on behavior and hippocampal monoamine neurotransmitter noradrenalin (NE), dopamine (DA) and 5-hydroxytrypamine (5-HT) contents in vascular dementia (VD) mice, so as to study its mechanism underlying improvement of VD.

Methods: A total of 60 Kunming mice were randomized into sham-operation control (n = 20), VD model (n = 20), EA-day (D)-1 (EA treatment was given from the 1st day on after modeling, n = 10), EA-D-3 (EA was given from the 3rd day on after modeling, n = 10) groups. VD model was established by occlusion of the bilateral cervical common arteries and reperfusion. EA (2 Hz/80 Hz) was applied to "Baihui" (GV 20), "Dazhui" (GV 14),"Zusanli" (ST 36) and "Geshu"(BL 17) for 10 min, once daily for 15 days. Hippocampal NE, DA and 5-HT contents were assayed by fluorospectrophotometry. The mouse's learning-memory ability was assessed by step-down tests.

Results: In comparison with the sham-operation control group, the learning-memory ability (marked increase of reaction time and error times, decrease of step-down latency) was apparently lowered in the model group (P < 0.01). The hippocampal NE, DA and 5-HT contents were significantly lower in the model group than in the sham-operation group (P < 0.01). Compared with the model group, the mice's learning-memory ability (marked decrease of reaction time and error times, increase of step-down latency) was significantly increased in EA intervention groups (P < 0.01), and hippocampal NE, DA and 5-HT levels were significantly increased (P < 0.01), and the effect of EA-D-3 group was obviously better than that of the EA-D-1 group (P < 0.05, P < 0.01).

Conclusion: EA can improve the VD mice's learning-memory ability, which is closely related to its effects in up-regulating hippocampal NE, DA and 5-HT contents, and the effect of later EA intervention after modeling is better.