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Acute abdomen in pregnancy
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Nicole Fearing, William L. Holcomb
Other physiologic changes may be attributed to hormonal changes associated with pregnancy such as the elevation in estrogen and progesterone levels. Several studies have shown that as levels of these hormones increase throughout pregnancy, orocecal motility slows. A study by Wald et al. showed that the gastrointestinal motility slowed by one-third during the third trimester of pregnancy compared with postpartum rates (6,7). It has also been shown that levels of the hormone motilin decrease. This affects the migrating motor complex also leading to slowed orocecal motility (8). The slowed transit can compound problems with constipation or other underlying abdominal pathology making diagnosis again more difficult. Progesterone has also been linked to decreased lower esophageal sphincter pressure and affects the urologic system. Dilation and slowing of peristalsis of the ureters have been associated with increase in progesterone. This may lead to urinary tract infection from urinary stasis (9,10).
The Small IntestineSecretions, Digestion and Motility
Published in Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal, Principles of Physiology for the Anaesthetist, 2020
Peter Kam, Ian Power, Michael J. Cousins, Philip J. Siddal
Segmentation and peristalsis are the two basic movements. In the fasting period, basal contractions due to migrating motor complex occur every 60–90 minutes, each contraction lasting for 10 minutes. These basal contractions generate intraluminal pressures of 4–12 mmHg.
Motilin and Gastric Inhibitory Polypeptide (GIP)
Published in Craig A. Johnston, Charles D. Barnes, Brain-Gut Peptides and Reproductive Function, 2020
Basal circulating levels of IRM in infants are higher than in adults (Christofides et al., 1978), but they gradually fall until the age of 20. While there is a postnatal surge in basal IRM to levels higher than those in adults (Lucas et al., 1982), there is no evidence for sex-related differences. The basal levels of motilin exhibit a cyclic pattern which is associated with the inter-digestive migrating motor complex (MMC) (Itoh et al., 1978a,b; Itoh, 1981; Peters et al., 1980). The relationship between these two phenomena will be discussed later.
Intragastric quinine administration decreases hedonic eating in healthy women through peptide-mediated gut-brain signaling mechanisms
Published in Nutritional Neuroscience, 2019
Julie Iven, Jessica R. Biesiekierski, Dongxing Zhao, Eveline Deloose, Owen G. O’Daly, Inge Depoortere, Jan Tack, Lukas Van Oudenhove
Distinguishing bitter taste allows detection of toxic compounds in food.1 However, some people have a preference for bitter taste, depending on their sensitivity to bitter compounds, which is sex-dependent, with women on average being more sensitive.1,2 Bitter tastants (i.e. chemicals stimulating the sense of taste) are sensed via taste receptors of the taste 2 receptor family (TAS2R) class of G-protein coupled receptors, located on taste receptor cells in lingual taste buds. However, TAS2Rs are also present on enteroendocrine cells (EEC) throughout the gastrointestinal (GI) tract.3 Activation of taste receptors on EECs occurs via a chemosensory signaling pathway and results in altered secretion of GI peptide hormones involved in the regulation of food intake.4 More specifically, TAS2Rs are present on ghrelin-producing X/A-like cells in the gastric fundus, among others. Ghrelin, a 28-amino acid peptide, is the key orexigenic GI hormone as its plasma levels peak pre-prandially and decrease rapidly with food ingestion.5 Motilin, a polypeptide hormone secreted by EECs in the duodenum, jejunum, and neurons of the myenteric plexus, is the regulator of the migrating motor complex (MMC), a cyclic secretomotor pattern during the fasted state that originates in the stomach and small bowel. Plasma motilin levels fluctuate with the phases of the MMC, and motilin-induced gastric phase III contractions coincide with increases in fasting hunger ratings, pointing towards an orexigenic effect of motilin.6,7
Alopecia areata and the gut—the link opens up for novel therapeutic interventions
Published in Expert Opinion on Therapeutic Targets, 2018
Normally, relatively few bacteria live in the small intestine (less than 10,000 bacteria per milliliter of fluid) as compared with the colon (at least 1,000,000,000 bacteria per milliliter of fluid) and the types of bacteria in the small intestine are not the same as those in the colon [18]. They play an important role in digesting food and absorbing nutrients but are also important regulators of the immune system with its impressive network of lymphoid cells in the intestinal submucosa. Moreover, the bacteria help maintain the normal muscular activity of the small bowel (Migrating Motor Complex, MMC). The MMC is responsible for moving the intestinal content through the gut, but most importantly, to clean the small intestine in between meals so that bacteria cannot overgrow. The MMC seems to be the most frequent dysfunction in people with SIBO [74] but also proper gastric acid secretion, biliary and pancreatic secretions, immunoglobulins in the intestinal fluid and the ileocecal valve (which allows the flow of bowel contents into the large intestine but prevents them from refluxing back into the small intestine) are important for an adequate small intestinal function [76].
Safety considerations when managing gastro-esophageal reflux disease in infants
Published in Expert Opinion on Drug Safety, 2021
Melina Simon, Elvira Ingrid Levy, Yvan Vandenplas
Erythromycin is a motilin receptor agonist that contributes to gastric emptying and induces phase III activity of the interdigestive migratory motor complex. Phase III, which is the most characteristic phase of the migrating motor complex, is the phase when the smooth muscle of the gastrointestinal tract rapidly contracts. In phase III, the pylorus remains open, allowing food to move into the small intestine [159].