Gastric mucosa

(Redirected from Stomach mucosa)

The gastric mucosa is the mucous membrane layer of the stomach, which contains the gastric pits, to which the gastric glands empty. In humans, it is about one mm thick, and its surface is smooth, soft, and velvety. It consists of simple secretory columnar epithelium, an underlying supportive layer of loose connective tissue called the lamina propria, and the muscularis mucosae, a thin layer of muscle that separates the mucosa from the underlying submucosa.

Gastric mucosa
Stomach
Section of mucous membrane of human stomach, near the cardiac orifice. X 45. c. Cardiac glands. d. Their ducts. cr. Gland similar to the intestinal glands, with goblet cells. mm. Mucous membrane. m. Muscularis mucosæ. m’. Muscular tissue within the mucous membrane.
Details
Identifiers
Latintunica mucosa gastris
MeSHD005753
TA98A05.5.01.027
TA22914
FMA14907
Anatomical terminology
Diagram of the alkaline mucous layer in the stomach with mucosal defense mechanisms

Description

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In its fresh state, it is of a pinkish tinge at the pyloric end and of a red or reddish-brown color over the rest of its surface. In infancy it is of a brighter hue, the vascular redness being more marked.

It is thin at the cardiac extremity, but thicker toward the pylorus. During the contracted state of the organ it is thrown into numerous folds or rugae, which, for the most part, have a longitudinal direction, and are most marked toward the pyloric end of the stomach, and along the greater curvature. These folds are entirely obliterated when the organ becomes distended.

When examined with a lens, the inner surface of the mucous membrane presents a peculiar honeycomb appearance from being covered with funnel-like depressions or foveolae of a polygonal or hexagonal form, which vary from 0.12 to 0.25 mm. in diameter. These are the ducts of the gastric glands, and at the bottom of each may be seen one or more minute orifices, the openings of the gland tubes. Gastric glands are simple or branched tubular glands that emerge on the deeper part of the gastric pits, inside the gastric areas and outlined by the folds of the mucosa.

Gastric glands

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The gastric glands in the cardiac region of the stomach are known as cardiac glands. In the pyloric region the glands are known as pyloric glands, and in the rest of the stomach they are called gastric glands.[1]

Several types of endocrine cells are found in the gastric glands. The pyloric glands contain gastrin-producing cells (G cells); this hormone stimulates acid production from the parietal cells. Enterochromaffin-like cells (ECLs), found in the oxyntic glands release histamine, which also is a powerful stimulant of the acid secretion.

Surface

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The surface of the mucous membrane is covered by a single layer of columnar epithelium. This epithelium commences very abruptly at the cardiac orifice, where there is a sudden transition from the stratified epithelium of the esophagus. The epithelial lining of the gland ducts is of the same character and is continuous with the general epithelial lining of the stomach.

The sodium-iodide symporter (SIP) is expressed in all the surface mucous cells (at the basolateral membrane) but not in the mucous neck cells. SIP mediates the transport of iodide from the bloodstream and secretes it into the gastric lumen where it is taken up in the gastric juice. Its role is not known but it has been shown to be absent in gastric cancer.[2]

Pathology

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See also

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References

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  This article incorporates text in the public domain from page 1166 of the 20th edition of Gray's Anatomy (1918)

  1. ^ Saladin, Kenneth S. (2011). Human anatomy (3rd ed.). New York: McGraw-Hill. pp. 665–666. ISBN 9780071222075.
  2. ^ Altorjay, Áron; Dohán, Orsolya; Szilágyi, Anna; Paroder, Monika; Wapnir, Irene L; Carrasco, Nancy (December 2007). "Expression of the Na+/l-symporter (NIS) is markedly decreased or absent in gastric cancer and intestinal metaplastic mucosa of Barrett esophagus". BMC Cancer. 7 (1): 5. doi:10.1186/1471-2407-7-5. PMC 1794416. PMID 17214887.
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