Effects of acupuncture at HT7 on glucose metabolism in a rat model of Alzheimer's disease: an (18)F-FDG-PET study

OBJECTIVE: To explore the effects of acupuncture at HT7 on different cerebral regions in a rat model of Alzheimer's disease (AD) with the application of (18)F-2-fluoro-deoxy-D-glucose positron emission tomography (FDG-PET). METHODS: Sixty Wistar rats were included after undergoing a Y-maze electric sensitivity test. Ten rats were used as a healthy control group. The remaining 50 rats were injected stereotaxically with ibotenic acid into the right nucleus basalis magnocellularis and injected intraperitoneally with D-galactose. AD was successfully modelled in 36 rats, which were randomly divided into three groups (n=12 each): the AD group, which remained untreated; the AD+HT7 group, which received 20 sessions of acupuncture at HT7 over 1 month; and the AD+Sham group, which received acupuncture at a distant non-acupuncture point. Total reaction time (TRT) was measured by Y-maze and (18)F-FDG-PET scans were conducted on day 1 and 30. PET images were processed with Statistical Parametric Mapping 8.0. RESULTS: Pre-treatment, TRT was greater in all AD groups versus controls (mean±SD 24.10±2.48 vs 41.34±5.00 s). Post-treatment, TRT was shortened in AD+HT7 versus AD+Sham and AD groups (p<0.0001, two-way analysis of variance). Glucose metabolic activity in the hippocampus, thalamus, hypothalamus, frontal lobe, and temporal lobe was decreased in AD rats compared with healthy controls and relatively elevated after HT7 acupuncture. Compared with sham acupuncture, HT7 needling had a greater positive influence on brain glucose metabolism. CONCLUSIONS: Needling at HT7 can improve memory ability and cerebral glucose metabolic activity of the hippocampus, thalamus, hypothalamus, and frontal/temporal lobes in an AD rat model.