American journal of physiology. Gastrointestinal and liver physiology
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Am. J. Physiol. Gastrointest. Liver Physiol. · Dec 2009
Randomized Controlled TrialCharacterizing the application of transcranial direct current stimulation in human pharyngeal motor cortex.
Transcranial direct current stimulation (tDCS) is a novel intervention that can modulate brain excitability in health and disease; however, little is known about its effects on bilaterally innervated systems such as pharyngeal motor cortex. Here, we assess the effects of differing doses of tDCS on the physiology of healthy human pharyngeal motor cortex as a prelude to designing a therapeutic intervention in dysphagic patients. Healthy subjects (n = 17) underwent seven regimens of tDCS (anodal 10 min 1 mA, cathodal 10 min 1 mA, anodal 10 min 1.5 mA, cathodal 10 min 1.5 mA, anodal 20 min 1 mA, cathodal 20 min 1 mA, Sham) on separate days, in a double blind randomized order. ⋯ There were neither contralateral hemisphere changes nor any evidence for ICI or ICF in driving the ipsilateral effects. In conclusion, anodal tDCS can alter pharyngeal motor cortex excitability in an intensity-dependent manner, with little evidence for transcallosal spread. Anodal stimulation may therefore provide a useful means of stimulating pharyngeal cortex and promoting recovery in dysphagic patients.
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Am. J. Physiol. Gastrointest. Liver Physiol. · Jun 2009
Randomized Controlled TrialDo corticotropin releasing factor-1 receptors influence colonic transit and bowel function in women with irritable bowel syndrome?
Corticotropin releasing factor (CRF), a mediator of stress response, alters gastrointestinal (GI) functions. Stress-related changes in colonic motility are blocked by selective CRF(1) receptor antagonists. Our aim was to assess whether modulation of central and peripheral CRF(1) receptors affects colonic transit and bowel function in female patients with diarrhea-predominant irritable bowel syndrome (D-IBS). ⋯ No safety issues were identified. We conclude that in women with D-IBS, pexacerfont, 25 or 100 mg qd, does not significantly alter colonic or other regional transit or bowel function. The role of central and peripheral CRF(1) receptors in bowel function in D-IBS requires further study.
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Am. J. Physiol. Gastrointest. Liver Physiol. · Aug 2004
Randomized Controlled Trial Clinical TrialEffect of oral CCK-1 agonist GI181771X on fasting and postprandial gastric functions in healthy volunteers.
CCK influences satiation and gastric and gallbladder emptying. GI181771X is a novel oral CCK-1 agonist; its effects on gastric emptying of solids, accommodation, and postprandial symptoms are unclear. Effects of four dose levels of the oral CCK-1 agonist GI181771X and placebo on gastric functions and postprandial symptoms were compared in 61 healthy men and women in a randomized, gender-stratified, double-blind, double-dummy placebo-controlled, parallel group study. ⋯ Adverse effects were predominantly gastrointestinal and occurred in a minority of participants. GI181771X delays gastric emptying of solids and exhibits an acceptable safety profile in healthy participants. CCK-1 receptors can be modulated to increase fasting gastric volume.