Relationship Between Gastric Acid Secretion, Histopathology, and Cell Proliferation Kinetics in Human Gastric Mucosa

We have previously identified cells containing the enzyme nitric oxide (NO) synthase (NOS) in the human gastric mucosa. Moreover, we have demonstrated that endogenous and exogenous NO has been shown to decrease histamine-stimulated acid secretion in isolated human gastric glands. The present investigation aimed to further determine whether this action of NO was mediated by the activation of guanylyl cyclase (GC) and subsequent production of cGMP. Isolated gastric glands were obtained after enzymatic digestion of biopsies taken from the oxyntic mucosa of healthy volunteers. Acid secretion was assessed by measuring [14C]aminopyrine accumulation, and the concentration of cGMP was determined by radioimmunoassay. In addition, immunohistochemistry was used to examine the localization of cGMP in mucosal preparations after stimulation with the NO donor S-nitroso- N-acetylpenicillamine (SNAP). SNAP (0.1 mM) was shown to decrease acid secretion stimulated by histamine (50 μM); this effect was accompanied by an increase in cGMP production, which was histologically localized to parietal cells. The membrane-permeable cGMP analog dibuturyl-cGMP (db-cGMP; 0.1–1 mM) dose dependently inhibited acid secretion. Additionally, the effect of SNAP was prevented by preincubating the glands with the GC inhibitor 4 H-8-bromo-1,2,4-oxadiazolo[3,4-d]benz[b][1,4]oxazin-1-one (10 μM). We therefore suggest that NO in the human gastric mucosa is of physiological importance in regulating acid secretion. Furthermore, the results show that NO-induced inhibition of gastric acid secretion is a cGMP-dependent mechanism in the parietal cell involving the activation of GC.

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Immunocytochemical identification of low-affinity NTS2 neurotensin receptors in parietal cells of human gastric mucosa

Journal of Endocrinology ◽

10.1677/joe.1.06903 ◽

2006 ◽

Vol 191 (1) ◽

pp. 121-128 ◽

Cited By ~ 5

Author(s):

Stefan Schulz ◽

Christoph Röcken ◽

Matthias P A Ebert ◽

Solveig Schulz

Keyword(s):

Plasma Membrane ◽

Gastric Mucosa ◽

Acid Secretion ◽

Gastric Acid Secretion ◽

Gastric Acid ◽

Parietal Cells ◽

Neuroendocrine Cells ◽

Target Cells ◽

Human Gastric Mucosa ◽

Western Blots

The biological effects of neurotensin (NT) are mediated by two distinct G protein-coupled receptors, NTS1 and NTS2. Although it is well established that neurotensin inhibits gastric acid secretion in man, the plasma membrane receptor mediating these effects has not been visualized yet. We developed and characterized a novel antipeptide antibody to the carboxy-terminal region of the human NTS2 receptor. The cellular and subcellular distribution of NTS2 receptors was evaluated in various human gastrointestinal tissues. Specificity of the antiserum was demonstrated by (1) detection of a broadband migrating at Mr 90 000–100 000 in Western blots of membranes from NTS2-expressing tissues; (2) cell-surface staining of NTS2-transfected cells; (3) translocation of NTS2 receptor immunostaining after agonist exposure; and (4) abolition of tissue immunostaining by preadsorbtion of the antibody with its immunizing peptide. In the gastrointestinal tract, NTS2 receptor immunoreactivity was highly abundant in parietal cells of the gastric mucosa, in neuroendocrine cells of the stomach small and large intestine, and in cells of the exocrine pancreas. NTS2 receptors were clearly located in the plasma membrane and uniformly present on nearly all target cells. The presence of NTS2 receptors was rarely detected in human tumors. This is the first localization of NTS2 receptors in human formalin-fixed, paraffin-embedded tissues at the cellular level. The abundant expression of low-affinity NTS2 receptors on the plasma membrane of human parietal cells provides a morphological substrate for the direct inhibition of gastric acid secretion observed after i.v. administration of neurotensin.

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An endoscopic method to investigate thf gastric acid secretion (VI) Studifs on biopsy specimens from human gastric mucosa

Gastroenterologia Japonica ◽

10.1007/bf02777908 ◽

1970 ◽

Vol 5 (1) ◽

pp. 84-84

Author(s):

H. Inui ◽

S. Okuda ◽

T. Saegusa ◽

J. Kojima ◽

T. Morii ◽

...

Keyword(s):

Gastric Mucosa ◽

Acid Secretion ◽

Gastric Acid Secretion ◽

Gastric Acid ◽

Human Gastric Mucosa ◽

Biopsy Specimens ◽

Endoscopic Method

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Effect of thyroid on gastric secretion and metabolism

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1961.201.3.567 ◽

1961 ◽

Vol 201 (3) ◽

pp. 567-570 ◽

Cited By ~ 12

Author(s):

E. S. Nasset ◽

Dale P. J. Goldsmith

Keyword(s):

Oxygen Consumption ◽

Gastric Mucosa ◽

Gastric Secretion ◽

Thyroid Hormones ◽

Acid Secretion ◽

Gastric Acid Secretion ◽

Gastric Acid ◽

Early Summer ◽

Tissue Concentrations ◽

Oxygen Ratio

The effect of administration of thyroid products on gastric acid secretion and metabolism was studied in dogs with gastric pouches and in gastric mucosa from rats and frogs. Whole thyroid, thyroxin, triiodothyronine, and iodinated casein generally reduced secretion in thyroidectomized dogs and in dogs with intact thyroids. The thyroid substances elevated BMR above euthyroid levels in normal dogs but not always in thyroidectomized dogs. In dogs with intact thyroids 2,4-dinitrophenol raised oxygen consumption but did not affect secretion. Whole thyroid elevated BMR in rats and frogs but did not change resting mucosal oxygen consumption. During spring and early summer thyroid feeding reduced histamine-stimulated acid secretion and mucosal oxygen consumption during secretion in frogs, but the acid-to-oxygen ratio was unaffected. These findings suggest that elevated tissue concentrations of thyroid hormones reduce the ability of the gastric mucosa to mobilize secretory energy in response to a stimulus. This effect of the thyroid hormones is apparently not directly correlated with their calorigenic properties.

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