Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society
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Neurogastroenterol. Motil. · Apr 2004
ReviewRole of peripheral CRF signalling pathways in stress-related alterations of gut motility and mucosal function.
Central corticotrophin releasing-factor (CRF) signalling pathways are involved in the endocrine, behavioural and visceral responses to stress. Recent studies indicate that peripheral CRF-related mechanisms also contribute to stress-induced changes in gut motility and intestinal mucosal function. Peripheral injection of CRF or urocortin inhibits gastric emptying and motility through interaction with CRF2 receptors and stimulates colonic transit, motility, Fos expression in myenteric neurones and defecation through activation of CRF1 receptors. ⋯ Similarly, early trauma enhanced intestinal mucosal dysfunction to an acute stressor in adult rats and the response is prevented by peripheral injection of CRF antagonist. Chronic psychological stress results in reduced host defence and initiates intestinal inflammation through mast cell-dependent mechanisms. These findings provide convergent evidence that activation of peripheral CRF receptors and mast cells are important mechanisms involved in stress-related alterations of gut physiology.
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Neurogastroenterol. Motil. · Apr 2004
Effect of high-frequency gastric electrical stimulation on gastric myoelectric activity in gastroparetic patients.
The aim of this study was to investigate the effect of gastric electrical stimulation (GES) on gastric myoelectric activity (GMA) and to identify possible mechanisms that could help explain how high-frequency GES is effective in treating nausea and vomiting associated with gastroparesis. Fifteen gastroparetic patients who received high-frequency GES were enrolled. Two pairs of temporary pacing wires were implanted on the serosa of the stomach along the greater curvature during surgery for placement of the permanent stimulation device. ⋯ A gastric emptying test and severity of nausea and vomiting were assessed at baseline and at 3 months of GES. Power spectral and cross correlation analyses revealed that impaired propagation of slow waves (50%), tachygastria (30%) and abnormal myoelectric responses to a meal (50%) were the main abnormalities observed at baseline. GES with a high frequency significantly enhanced the slow wave amplitude and propagation velocity, and resulted in a significant improvement in nausea and vomiting but did not entrain the gastric slow wave or improve gastric emptying after 3 months of GES.