[Study on influence of acupunctural signal on energy metabolism of human brain by positron emission tomography].

Objective: To study the biologic process of energy metabolism in brain during acupuncture using positron emission tomography (PET) with 18F-2-desoxyglucose (18FDG) for further elucidation of the relationship between acupunctural signal and nerve system.

Methods: Electroacupuncture (EA) was applied on right lateral of a healthy volunteer and paralytic limbs of 4 patients with cerebral infarction at acupoints L14, LI11, ST36 and SP6 using Hans acupoint-nerve stimulator. PET imaging was conducted on the healthy subject or patients with the same posture before and during EA with GE Advance II PET system.

Results: PET showed that in the healthy subject, before EA, the glucose metabolism (GM) in bilateral cerebral cortex, bilateral thalamus, basal nuclei and cerebellum was almost symmetrical, but during EA, the GM in contralateral thalamus, contralateral frontal lobe and parietal lobe (motor and sensory area) increased obviously. While in the patients before EA, the GM in the infarcted area was significantly lower than that in the non-infarcted area, as compared with that observed with CT and MRI, it showed a similar figure but with bigger abnormal area. During EA, GM in the infarcted area increased with apparent reduction of size. Increased GM of focal area, widened cerebral cortex and decreased edematous area were shown in patients with larger infarction area. Quantitative analysis revealed evident change in local/total ratio of glucose and increase of GM change rate.

Conclusion: (1) EA on limb acupoints of healthy subject could induce obvious increase of regional GM in brain and contralateral thalamus, contralateral frontal lobe and parietal lobe (motor and sensory area). (2) EA on acupoints of paralytic limbs could cause increase of GM in contralateral thalamus, contralateral frontal lobe and parietal lobe. Besides, GM also increased in the area with lowered GM before EA, accompanied with shrinkage or disappearance of lesion. (3) Acupuncture could evoke the function of brain cells and raise the GM in them.