ArticleAmerican journal of physiology. Gastrointestinal and liver physiology2009
Luminal L-glutamate enhances duodenal mucosal defense mechanisms via multiple glutamate receptors in rats.
Article in American journal of physiology. Gastrointestinal and liver physiology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 46 papers.
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Who cites it
46 citing papers in PubMed, 106 citations in OpenAlex.
- Review
- The Enteric Neuronal Circuitry: A Key Ignored Player in Nutrient Sensing Along the Gut-Brain Axis.FASEB journal : official publication of the Federation of American Societies for Experimental Biology · 2025Review
- Postoral receptors and alimentary taste: implications for energy intake and appetite.Chemical senses · 2025Review
- Gut microbiota and stress ulcers: unraveling the neurotransmitter connection.Frontiers in neuroscience · 2025Review
- The flavor-enhancing action of glutamate and its mechanism involving the notion of kokumi.NPJ science of food · 2023Review
- Article
- Glutamate attenuates lipopolysaccharide induced intestinal barrier injury by regulating corticotropin-releasing factor pathway in weaned pigs.Animal bioscience · 2022Article
- Luminal Chemosensory Cells in the Small Intestine.Nutrients · 2021Review
- Invited Review: Maintain or Improve Piglet Gut Health around Weanling: The Fundamental Effects of Dietary Amino Acids.Animals : an open access journal from MDPI · 2021Review
- Nutrient-Induced Cellular Mechanisms of Gut Hormone Secretion.Nutrients · 2021Review
- The Modulation of Pain by Metabotropic Glutamate Receptors 7 and 8 in the Dorsal Striatum.Current neuropharmacology · 2020Review
- Glutamatergic Signaling Along The Microbiota-Gut-Brain Axis.International journal of molecular sciences · 2019Review
- Regulation of Ion Transport in the Intestine by Free Fatty Acid Receptor 2 and 3: Possible Involvement of the Diffuse Chemosensory System.International journal of molecular sciences · 2018Review
- Luminal chemosensing in the gastroduodenal mucosa.Current opinion in gastroenterology · 2017Review
- FFA2 activation combined with ulcerogenic COX inhibition induces duodenal mucosal injury via the 5-HT pathway in rats.American journal of physiology. Gastrointestinal and liver physiology · 2017Article
- Neurochemical Markers in the Mammalian Brain: Structure, Roles in Synaptic Communication, and Pharmacological Relevance.Current medicinal chemistry · 2017Review
- Flavor Preferences Conditioned by Dietary Glutamate.Advances in nutrition (Bethesda, Md.) · 2016Review
- The Emerging Role of Metabotropic Glutamate Receptors in the Pathophysiology of Chronic Stress-Related Disorders.Current neuropharmacology · 2016Review
- The Neuro-endocrinological Role of Microbial Glutamate and GABA Signaling.Frontiers in microbiology · 2016Review
- Chemosensory signalling pathways involved in sensing of amino acids by the ghrelin cell.Scientific reports · 2015Article
Corrections and comments
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Authors and funding
4 authors at 3 institutions in 1 country.
Funding
Abstract
Presence of taste receptor families in the gastrointestinal mucosa suggests a physiological basis for local and early detection of a meal. We hypothesized that luminal L-glutamate, which is the primary nutrient conferring fundamental umami or proteinaceous taste, influences mucosal defense mechanisms in rat duodenum. We perfused the duodenal mucosa of anesthetized rats with L-glutamate (0.1-10 mM). Intracellular pH (pH(i)) of the epithelial cells, blood flow, and mucus gel thickness (MGT) were simultaneously and continuously measured in vivo. Some rats were pretreated with indomethacin or capsaicin. Duodenal bicarbonate secretion (DBS) was measured with flow-through pH and CO(2) electrodes. We tested the effects of agonists or antagonists for metabotropic glutamate receptor (mGluR) 1 or 4 or calcium-sensing receptor (CaSR) on defense factors. Luminal L-glutamate dose dependently increased pH(i) and MGT but had no effect on blood flow in the duodenum. L-glutamate (10 mM)-induced cellular alkalinization and mucus secretion were inhibited by pretreatment with indomethacin or capsaicin. L-glutamate effects on pH(i) and MGT were mimicked by mGluR4 agonists and inhibited by an mGluR4 antagonist. CaSR agonists acidified cells with increased MGT and DBS, unlike L-glutamate. Perfusion of L-glutamate with inosinate (inosine 5'-monophosphate, 0.1 mM) enhanced DBS only in combination, suggesting synergistic activation of the L-glutamate receptor, typical of taste receptor type 1. L-leucine or L-aspartate had similar effects on DBS without any effect on pH(i) and MGT. Preperfusion of L-glutamate prevented acid-induced cellular injury, suggesting that L-glutamate protects the mucosa by enhancing mucosal defenses. Luminal L-glutamate may activate multiple receptors and afferent nerves and locally enhance mucosal defenses to prevent subsequent injury attributable to acid exposure in the duodenum.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.