Two-Channel Gastric Electrical Stimulation Accelerates Delayed Gastric Emptying Induced by Vasopressin

Abstract

The aim of this study was to investigate the effects of two-channel gastric electrical stimulation (GES) on delayed gastric emptying, gastric dysrhythmias, and motion sickness-like symptoms induced by vasopressin. Seven dogs implanted with four pairs of gastric electrodes and a duodenal cannula were studied in four randomized sessions (saline, vasopressin, single-channel GES, and two-channel GES). The experiment in each session was conducted sequentially as follows: 30-min baseline, ingestion of a liquid meal, 30-min iv infusion of vasopressin or saline, and two 30-min postprandial recordings. In the GES sessions, GES was applied via the first pair of electrodes for single-channel GES or the first and third pairs of electrodes for two-channel GES. Gastric emptying was collected every 15 min via the cannula for a period of 90 min. Results were as follows. (1) Vasopressin induced gastric dysrhythmias, motion sickness-like symptoms, and delayed gastric emptying (P < 0.01, ANOVA). (2) GES normalized gastric dysrhythmias (P < 0.01) but showed no effects on vasopressin-induced emetic response. (3) Two-channel GES improved delayed gastric emptying induced by vasopressin. In comparison with the vasopressin session, two-channel GES, but not single-channel GES, significantly increased gastric emptying at 30 min (43.9+/-12.6 vs. 27.5+/-7.7%; P < 0.03), 60 min (75.3+/-15.1 vs. 54.0+/-17.8%; P < 0.05), and 90 min (91.6+/-9.8 vs. 80.3+/-9.0%; P < 0.05). GES with long pulses is able to normalize gastric dysrhythmias. Two-channel GES improves delayed gastric emptying induced by vasopressin.

Systematic review: applications and future of gastric electrical stimulation

“…It seems that a single channel GES with long pulses has no effects on gastric emptying in healthy dogs but is capable of improving gastric emptying in a canine model of gastroparesis and a rodent model of diabetes. 29,34,50 Whereas, two-or four-channel GES with long pulses is able to improve gastric emptying in both healthy and diseased model of canines; 21,22 similar results (improvement in liquid and solid gastric emptying) were also observed with a multi-channel sequential GES of trains of pulses with a pulse width in the order of a few milliseconds. 23,24 GES with long pulses showed similar improvement in gastric emptying in patients with gastroparesis.…”

“…Two-to four-channel GES has been proposed in a number of studies. [21][22][23][24] Peripheral effects of GES A number of studies have been performed to investigate the effect of GES on the normalization of gastric myoelectrical dysrhythmias or entrainment of gastric slow waves, fundic/antral tone, antral contractions and gastric emptying. The majority of these studies seems to indicate that GES, depending on the parameters employed and stimulation sites, is able to alter gastric functions.…”

Electroacupuncture improves impaired gastric motility and slow waves induced by rectal distension in dogs

“…The 1-min recording was categorized as normal if the peak power was within the 4 -6 cpm range; otherwise it was categorized as dysrhythmia. The definition of the normal frequency range of 4 -6 cpm in the stomach was based on our previous study (40).…”

537 Long-Term Effects of Gastric Stimulation on Gastric Electrical Physiology

“…6,[10][11][12][13][14][15][16] Several novel GES methods to improve gastric motility have been introduced over the last 20 years, such as multichannel GES, dual-pulse GES, and synchronized GES. [17][18][19][20][21][22][23][24][25][26] The term "gastric neuromodulation" has been used as a term to describe the antiemetic effect of GES therapy, as the symptom improvement is believed to be mediated through neurons and neuronal connectivity. A number of GES studies have demonstrated that gastric slow-wave pacing has entrained these slow waves with the pulse rates of the GES device.…”

“…A number of GES studies have demonstrated that gastric slow-wave pacing has entrained these slow waves with the pulse rates of the GES device. 17,18,20,[27][28][29] Not much is known about the long-term changes of gastric neurophysiology after chronic GES therapy. It has been shown that GES therapy is not effective in improvement of gastric dysrhythmia.…”