Effects of electro-acupuncture at LI4 with Deqi compared to Sham acupuncture on blood flow in the middle cerebral artery of healthy subjects

IntroductionAcupuncture has been suggested to improve dysfunctions caused by disturbances in cerebral blood flow. However, the scientific basis of this acupuncture practice remains unresolved.AimThis study aims to explore whether EA with Deqi sensation might exert different response in middle cerebral artery (MCA).MethodsEleven healthy subjects were continuously monitored for the blood flow velocity (BFV) of both MCA with transcranial Doppler before, during and after EA, while either left Hegu or Sham points were applied. Heart rate was calculated and measured. The needle remained inserted for 20 min, and post-stimulus resting recordings were taken for additional 10 min. The subjects rated the EA effects that they experienced at the end of the experiment.ResultsBoth real and Sham EA groups experienced the Deqi sensation, and the Deqi score of those receiving Sham EA was not significantly different from those receiving real EA. Application of EA at Hegu caused a significant decrease in ipsilateral blood flow velocity and further decreased in the post-stimulation period. The Sham EA did not alter the value of both BFVs during the stimulation period, but in comparison with the stimulation period, it caused significant decrease in both BFVs during the post-stimulation period. The EA of either Hegu or Sham point resulted in a statistically significant decrease in the heart rate during stimulation and post-stimulation periods.ConclusionEA at Hegu generally led to a significant decrease in the ipsilateral BFV of MCA during the stimulation period and post-stimulation period, in normal healthy subjects.