PET Imaging of Glucose Metabolic Response in Human Brain Induced by Stimulation of Acupoint ST36

Xianglan Jin1, Yilong Ma2, Jintao Zhang1, Yigen Wu3, Baoci Shan3, Dayi Yin1, Jinping Sun1, Xian Shi1, Jiahe Tian1, Shulin Yao1, Bo Yu4, Ling Yin1
1Neuroinformatics Center, PLA General Hospital, Beijing, China
2Department of Neurology, New York University School of Medicine, New York, USA
3Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China

4 No. 202 Hospital of PLA, Shenyang City, Liaoning Province China

 

Objective: Functional magnetic resonance imaging (fMRI) has been increasingly used for understanding the specific central mechanism of acupuncture in normal human subjects [1, 2]. A few imaging studies have also examined brain activation responses by measuring cerebral blood flow with positron emission tomography (PET) [3, 4]. However the modulation effect of acupuncture on brain metabolism has not been investigated. The aim of this work is to explore the experimental method of PET imaging to map changes in cerebral metabolic function induced by puncturing the Stomach 36 (ST36, Zusanli). It is known that this acupoint has been employed clinically as an alternative therapy in the management of functional gastrointestinal disorders [5].
Methods: PET brain images were acquired on six healthy volunteers (age: 27.2+/-2.3 years; right-handed males) with [18F]-fluorodeoxyglucose (FDG). This was performed in 3D mode on a Siemens HR+ PET as baseline with a placebo needle, and after the puncturing of the ST36 acupoint (the right leg). The placebo and acupuncture scans were separated by one week. Images of cerebral glucose metabolism were realigned and spatially normalized into Talairach space. Statistical parametric mapping (SPM) was then used to localize brain areas with both increased and decreased metabolic changes relative to the baseline. The area was considered significant with a threshold of p < 0.01 as our analysis was hypothesis driven.
Results & Discussion: Stimulation of acupoint ST36 resulted in significantly increased glucose metabolism in the left precentral and postcentral gyru, superior and middle temporal gyru, cerebellum and hypothalamus, right medial and superior frontal gyru (Table 1), while decreased in the right inferior frontal, middle occipital and temporal gyru, cingulate gyrus and cerebellum, left middle occipital gyrus, precuneus, cerebellum and lentiform nucleus. This set of areas was mostly in good agreement with early observations made by fRMI and PET experiments [3, 6].
Conclusions: This study shows the first evidence of brain metabolic modulation by acupuncture in human subjects. Acupunctuing ST36 seems to increase glucose metabolism in pain related brain regions. Metabolic changes are also seen in different parts of the autonomic nerve system, which is correlated to gastric function. This method may provide more direct insights into the therapeutical mechanism of acupuncture in traditional Chinese medicine.