Potential of intestinal electrical stimulation for obesity: a preliminary canine study.

Veterans Research and Education Foundation, Veterans Administration Medical Center, Oklahoma City, Oklahoma, USA.
Obesity (Impact Factor: 4.39). 05/2007; 15(5):1133-8. DOI: 10.1038/oby.2007.615
Source: PubMed

ABSTRACT The aims of this study were to investigate the therapeutic potential of intestinal electrical stimulation (IES) for obesity. Experiments were performed to investigate the effects of IES on food intake, gastric tone, gastric accommodation, and its possible pathway.
Ten normal dogs and six dogs with truncal vagotomy were used in this study. Each dog was equipped with a gastric cannula for the measurement of gastric tone and accommodation by barostat and one pair of duodenal serosal electrodes for IES. The experiment on food intake was composed of both control session without IES and IES session after a 28-hour fast. The experiment on gastric tone and accommodation was performed in the fasting and fed states and composed of three sessions: control, IES, and IES with N(G)-nitro-l-arginine.
IES significantly reduced food intake in the normal dogs (459.0 vs. 312.6 grams, p < 0.001). The food intake was negatively correlated with the fasting gastric volume during IES. IES significantly decreased fasting gastric tone in the normal dogs reflected as a decrease in gastric volume (89.1 vs. 261.3 mL, p < 0.01), which was abolished by vagotomy and N(G)-nitro-l-arginine.
IES reduces food intake and inhibits gastric tone in the fasting state. The inhibitory effect of IES on gastric tone is mediated by both vagal and nitrergic pathway.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Journal of Medical Diagnostic Methods 01/2014; 03(02). DOI: 10.4172/2168-9784.1000e110
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study tested the effects of the gastrointestinal pulse train electrical stimulation with different parameters and at different locations on the neuronal activities of the lateral hypothalamus area (LHA) in obese rats in order to find the optimal stimulation parameter and location. Eight gastric electrical stimulations (GES) with different parameters were performed and the neuronal activities of gastric-distension responsive (GD-R) neurons in LHA were observed. The effects of stimulations with 8 parameters were compared to find the optimal parameter. Then the optimal parameter was used to perform electrical stimulation at duodenum and ileum, and the effects of the duodenal and ileac stimulation on the GD-R neurons in LHA were compared with the gastric stimulation of optimal parameter. The results showed that GES with the lowest energy parameter (0.3 ms, 3 mA, 20 Hz, 2 s on, 3 s off) activated the least neurons. The effects of GES with other parameters whose pulse width was 0.3 ms were not significantly different from those of the lowest energy parameter. Most gastric stimulations whose pulse width was 3 ms activated more LHA neurons than the smallest energy parameter stimulation, and the effects of those 3 ms gastric stimulations were similar. Accordingly, the lowest energy parameter was recognized as the optimal parameter. The effects of stimulations with the optimal parameter at stomach, duodenum and ileum on the LHA neuronal activities were not different. Collectively, gastrointestinal electrical stimulation (GIES) with relatively large pulse width might have stronger effects to the neuronal activities of GD-R neurons in LHA of obese rats. The effects of the GIES at different locations (stomach, duodenum and ileum) on those neurons are similar, and GES is preferential because of its easy clinical performance and safety.
    Journal of Huazhong University of Science and Technology 08/2014; 34(4):510-5. DOI:10.1007/s11596-014-1307-z · 0.78 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mirtazapine is a noradrenergic and specific serotonergic antidepressant. The aim of this study was to investigate the effects of mirtazapine on gastrointestinal motility in dogs, including solid gastric emptying, antral and small intestinal contractions, small intestinal and colonic transit. Methods: Six dogs were implanted with two cannulas located at the duodenum and the ascending colon; Another 6 dogs were implanted with gastric cannula 6cm proximal to the pylorus. Mirtazapine 45mg was administered orally 90 minutes before the study. Results: 1). Mirtazapine accelerated gastric emptying during the entire 3 hours in normal dogs (P < 0.04) and accelerated delayed gastric emptying induced by rectal distention (P < 0.04). 2). Mirtazapine restored impaired gastric tone and accommodation induced by rectal distention (P < 0.05) 3) No significant changes were noted in small intestinal contractions or transit with mirtazapine (P > 0.1). 4). Mirtazapine accelerated colonic transit at 2 and 4 hours but not 6 hours. The geometric center (GC) was increased from 1.9 ± 0.6 to 3.0 ± 0.5, 3.9 ± 0.5 to 4.7 ± 0.1 at 2 and 4 hours respectively (P = 0.04 vs. corresponding control). Conclusions: Mirtazapine improves gastric emptying in healthy dogs and normalizes rectal distention-induced delay in gastric emptying and accelerates colon but not small intestinal transit in healthy dogs. Clinical studies are warranted to assess the effects of mirtazapine on gastrointestinal motility and sensory functions in patients with functional GI diseases.
    AJP Gastrointestinal and Liver Physiology 03/2014; 306(9). DOI:10.1152/ajpgi.00130.2013 · 3.74 Impact Factor