Effects of the acupoints PC 6 Neiguan and LR 3 Taichong on cerebral blood flow in normal subjects and in migraine patients

Acupuncture has been proven to be effective in the treatment of various cardiovascular disorders; it acts both on the peripheral flow and on the cerebral flow. Our study aimed to evaluate the effects of the insertion of PC 6 Neiguan and LR 3 Taichong acupoints on the cerebral blood flow (CBF) in the middle cerebral artery (MCA). These effects were measured in a group of patients suffering from migraine without aura (Group M) and in a healthy control group (Group C). In the study, we included 16 patients suffering from migraine without aura, classified according to the criteria of the International Headache Society, and 14 healthy subjects as a control group. The subjects took part in the study on two different days, and on each day, the effect of a single acupoint was evaluated. Transcranial Doppler was used to measure the blood flow velocity (BFV) in the MCA. Our study showed that the stimulation of PC 6 Neiguan in both groups results in a significant and longlasting reduction in the average BFV in the MCA. After pricking LR 3 Taichong, instead, the average BFV undergoes a very sudden and marked increase; subsequently, it decreases and tends to stabilize at a slightly higher level compared with the baseline, recorded before needle insertion. Our data seem to suggest that these two acupoints have very different effects on CBF. The insertion of PC 6 Neiguan probably triggers a vasodilation in MCA, while the pricking of LR 3 Taichong determines a rapid and marked vasoconstriction.