Therapeutic potential of gastric electrical stimulation for obesity and its possible mechanisms: a preliminary canine study.

Our aim was to investigate the effects of gastric electrical stimulation on food intake, weight, gastric myoelectrical, and parasympathetic activity. Dogs were implanted with serosal electrodes and a subcutaneous stimulator. The stimulator was turned on and off alternately every month for 4 months. Food intake, weight, gastric myoelectrical activity, and electrocardiograms were recorded. Daily food intake and weight were significantly decreased during the months with stimulation. Stimulation did not show any acute effect on gastric myoelectrical activity; however, it chronically and significantly impaired gastric myoelectrical activity in the fed state, but not in the fasting state. The parasympathetic activity in the fasting state assessed from the spectral analysis of heart rate variability was markedly decreased with stimulation both acutely and chronically. In conclusion, chronic gastric electrical stimulation results in a reduction in food intake, weight loss, a reduction in parasympathetic activity, and chronic inhibition of gastric myoelectrical activity. These data suggest that gastric electrical stimulation is a potential therapy for the treatment of obesity and its inhibitory effect on food intake and weight may involve both muscles and the vagal afferent pathway.