Free and conjugated catecholamines in digestive tissues of rats

Gaudin, Christophe; Ruget, G; Selz, Françoise; Cuche, Jean-Louis

doi:10.1016/0024-3205(85)90177-8

Cited by 26 publications

(5 citation statements)

References 14 publications

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“…It is interesting to note that certain peptidergic cells of the amine precursor uptake and carboxylation series within the gut may have dopaminergic precursors (54). High quantities of both free and conjugated DA along with DA metabolites are present within mesenteric organs (8,11,12,17). These findings have prompted the hypothesis that the GIT is an integral component of a peripheral catecholaminergic system, wherein DA acts as an autocrine or paracrine hormone being inactivated by conjugation (21).…”

Section: Discussionmentioning

confidence: 99%

“…DA is thought to mediate, in part, so-called gastric adaptive cryoprotection, a phenomenon wherein application of a mild irritant to the gastric mucosal surface confers protection against subsequent irritant exposures (33). Significant levels of DA are demonstrable within gastric mucosa (11,17), and ligand-binding studies have revealed D 1like receptors in both rat (8,22) and human gastric mucosa (24). Immunohistochemical studies have revealed substantial reductions in gastric mucosal DA content with acute ulceration (25).…”

Section: Discussionmentioning

confidence: 99%

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Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract

Vaughan

Aherne

Lane

et al. 2000

American Journal of Physiology-Regulatory, Integrative and Comp

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Dopamine (DA) is regarded as an important modulator of enteric function. Recent experiments have suggested that newly cloned DA receptor subtypes are widely expressed in peripheral organs, including the gastrointestinal tract. In the present studies, the D(1A) receptor subtype was identified in rat gut regions through localization of receptor protein by means of light microscopic immunohistochemistry and Western blot analysis and receptor mRNA by RT-PCR and in situ amplification and hybridization (3SR in situ). D(1A) receptor immunoreactivity was shown to have a diverse distribution in the gastrointestinal tract, being present in the gastroesophageal junction, stomach, pylorus, small intestine, and colon. The receptor has a transmural distribution present in both epithelial and muscle layers as well as in blood vessels and lamina propria cells of different gastrointestinal regions. Western blot analysis demonstrated a single 50-kDa band for esophagus, stomach, duodenum, jejunum, and colon. The in situ hybridization signal was localized to the same sites revealed by D(1A) receptor immunoreactivity. RT-PCR revealed an appropriate sized signal in similar regions. This study is the first to identify expression of the central D(1A) receptor throughout the normal mammalian gastrointestinal tract.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract

Vaughan

Aherne

Lane

et al. 2000

American Journal of Physiology-Regulatory, Integrative and Comp

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“…Dopamine is present in the human nervous system and acts directly on specific central and peripheral receptors [1]. There are significant amounts of dopamine in the gastrointestinal tract, accounting for up to 20% of the free catecholamine content in the stomach [2]. Studies in dogs and volunteers have shown that dopamine decreases stomach muscle tone and it has been proposed as a possible neurotransmitter in gastric relaxation [3, 4].…”

Section: Introductionmentioning

confidence: 99%

Dopamine delays gastric emptying and prolongs orocaecal transit time in volunteers

1999

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Dopamine decreases gastric tone and may therefore influence gastrointestinal motility. The aim of this investigation was to study the effects of a continuous infusion of dopamine on gastric emptying and orocaecal transit time. Nine healthy male volunteers were studied on two occasions in a randomized order. All volunteers received on separate days a continuous infusion of dopamine 5 micrograms kg-1 min-1 on one occasion and normal saline on the other occasion. Gastric emptying was measured by the paracetamol absorption test and orocaecal transit time by the hydrogen breath test. During the dopamine infusion the area under the paracetamol concentration curve was significantly smaller than during control conditions (P = 0.02). Orocaecal transit time was prolonged during the dopamine infusion (P = 0.02). Dopamine delays gastric emptying and prolongs orocaecal transit time.

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“…The majority of CA [NE, Epi, dopamine (DA)] found in blood and urine is conjugated (glucuronide- or sulfate-conjugated) and biologically inactive (Yoneda et al, 1983; Gaudin et al, 1985). Free CA as well as sulfotransferase enzymes, which conjugate free CA, are gradually distributed in the gut with the lowest concentration in the stomach and highest concentration in the large intestine, which correlates with bacterial loads in these organs (Harris et al, 2000; Asano et al, 2012).…”

Section: Multidirectional Signaling In the Gut And Effect On S Typhimentioning

confidence: 99%

Salmonella Typhimurium and Multidirectional Communication in the Gut

et al. 2016

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The mammalian digestive tract is home to trillions of microbes, including bacteria, archaea, protozoa, fungi, and viruses. In monogastric mammals the stomach and small intestine harbor diverse bacterial populations but are typically less populated than the colon. The gut bacterial community (microbiota hereafter) varies widely among different host species and individuals within a species. It is influenced by season of the year, age of the host, stress and disease. Ideally, the host and microbiota benefit each other. The host provides nutrients to the microbiota and the microbiota assists the host with digestion and nutrient metabolism. The resident microbiota competes with pathogens for space and nutrients and, through this competition, protects the host in a phenomenon called colonization resistance. The microbiota participates in development of the host immune system, particularly regulation of autoimmunity and mucosal immune response. The microbiota also shapes gut–brain communication and host responses to stress; and, indeed, the microbiota is a newly recognized endocrine organ within mammalian hosts. Salmonella enterica serovar Typhimurium (S. Typhimurium hereafter) is a food-borne pathogen which adapts to and alters the gastrointestinal (GI) environment. In the GI tract, S. Typhimurium competes with the microbiota for nutrients and overcomes colonization resistance to establish infection. To do this, S. Typhimurium uses multiple defense mechanisms to resist environmental stressors, like the acidic pH of the stomach, and virulence mechanisms which allow it to invade the intestinal epithelium and disseminate throughout the host. To coordinate gene expression and disrupt signaling within the microbiota and between host and microbiota, S. Typhimurium employs its own chemical signaling and may regulate host hormone metabolism. This review will discuss the multidirectional interaction between S. Typhimurium, host and microbiota as well as mechanisms that allow S. Typhimurium to succeed in the gut.

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Free and conjugated catecholamines in digestive tissues of rats

Cited by 26 publications

References 14 publications

Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract

Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract

Dopamine delays gastric emptying and prolongs orocaecal transit time in volunteers

Salmonella Typhimurium and Multidirectional Communication in the Gut

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Free and conjugated catecholamines in digestive tissues of rats

Cited by 26 publications

References 14 publications

Identification and regional distribution of the dopamine D1A receptor in the gastrointestinal tract

Identification and regional distribution of the dopamine D1A receptor in the gastrointestinal tract

Dopamine delays gastric emptying and prolongs orocaecal transit time in volunteers

Salmonella Typhimurium and Multidirectional Communication in the Gut

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Product

Resources

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Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract

Identification and regional distribution of the dopamine D_1A receptor in the gastrointestinal tract