Acupuncture Stimulation at Baihui Acupoint Reduced Cerebral Infarct and Increased Dopamine Levels in Chronic Cerebral Hypoperfusion and Ischemia-Reperfusion Injured Sprague-Dawley Rats

Abstract
The Baihui acupoint has three Yang and five convergences; it is needled in order to activate spirit and resuscitate the brain in traditional Chinese medicine. Therefore, the purpose of the present study is to investigate the effect of acupuncture stimulation at the Baihui acupoint on cerebral infarct and dopamine levels. A chronic cerebral hypoperfusion animal model was established by permanent ligation of both common carotid arteries; a cerebral infarct animal model was established by blocking the blood flow of both common carotid arteries and the right middle cerebral artery for 90 min followed by reperfusion in Sprague-Dawly (SD) rats. The Baihui acupoint was stimulated for 20 min 3 days per week for 4 weeks. The cognitive and memory functions were evaluated by measuring the successful rates for rats to negotiate an 8-arm radial maze test; the test was performed after operation once a week for 4 weeks. Finally, the rats were sacrificed and their brains were removed; the dopamine levels in brain tissue were measured and the percentage of right to left hemisphere area was calculated. The results indicated that acupuncture stimulation (AS) did not increase the success rate of performing the 8-arm radial maze in chronic cerebral hypoperfusion and cerebral ischemia-reperfusion injured rat models. AS increased dopamine levels in the right cerebral cortex and hippocampus in the chronic cerebral hypoperfusion rats, and increased dopamine levels of the cerebral cortex in the cerebral ischemia-reperfusion injured rat's models. The neurological deficit score was similar between control and AS groups 24 hours after reperfusion, whereas the AS group comprised of ischemia-reperfusion injured rats had a greater percentage of right to left hemisphere area than the control group. In conclusion, AS at the Baihui acupoint for 4 weeks increased dopamine levels in the brain tissue of chronic cerebral hypoperfusion rats and of cerebral ischemia-reperfusion injured rats. The AS also reduced brain atrophy after cerebral infarct, suggesting that AS at the Baihui acupoint acts as neuroprotector. However, regular stimulation at the Baihui acupoint enhances cognition and memory functions need further study.