Hippocampal deep brain stimulation reduces glucose utilization in the healthy rat brain.

Purpose: The effects of deep brain stimulation (DBS) have been studied primarily by cellular studies, which lack the ability to elucidate DBS-related responses on a whole-brain scale. 2-Deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography ([(18)F]FDG-PET) reflects changes in neural activity throughout the entire brain volume. The aim of this study was to investigate the whole-brain effect of DBS on the glucose utilization in healthy rats.

Procedures: Seven rats were implanted with a DBS electrode in the right hippocampus and injected with [(18)F]FDG to measure the glucose metabolism during DBS.

Results: Analysis reveals significant DBS-induced decreases in the glucose metabolism in the bilateral hippocampus and other limbic structures.

Conclusions: This study demonstrates that DBS exhibits not only a local effect around the electrode tip but also in other limbic regions. [(18)F]FDG-PET studies have the potential to provide better insight into the mechanism of action of DBS by simultaneously observing activity at multiple sites in the brain.