| Foveolar cells | |
|---|---|
 Microscopic section of gastric mucosa. Foveolar cells can be seen at top of the image lining the surface and pits | |
| Details | |
| Location | Stomach |
| Function | Mucus production |
| Identifiers | |
| Latin | mucocytus superficialis |
| TH | H3.04.02.1.00023 |
| Anatomical terms of microanatomy | |
Foveolar cells orsurface mucous cells aremucus-producingcells which cover the inside of thestomach, protecting it from the corrosive nature ofgastric acid.[1][a] These cells line thegastric mucosa and the gastric pits.Mucous neck cells are found in the necks of thegastric glands. The mucus-secreting cells of the stomach can be distinguished histologically from the intestinalgoblet cells, another type of mucus-secreting cell.
Thegastric mucosa that lines the inner wall of thestomach has a set of microscopic features called gastric glands which, depending on the location within the stomach, secrete different substances into thelumen of the organ. The openings of these glands into the stomach are calledgastric pits which foveolar cells line in order to provide a protective alkaline secretion against the corrosivegastric acid.[2]: 256
Foveolar cells line the surface of the stomach and the gastric pits. They constitute asimple columnar epithelium, as they form a single layer of cells and are taller than their width. Other mucus-secreting cells are the mucous neck cells in the necks of the gastric glands.[2]: 257
Surface mucous cells have large quantities ofmucin granules in theirapical (top) surface and project shortmicrovilli into thelumen of the stomach.[2]: 257 Mucins are largeglycoproteins that give the mucus its gel-like properties.[3] As mucins are lost during routinehistology preparation, they stain pale, but if preserved correctly the cells stain strongly with special techniques likePAS ortoluidine blue, the last representing theanionic nature of foveolar cell secretions. Below the mucin granules, surface mucous cells have aGolgi apparatus, thenucleus, and small amounts ofrough endoplasmic reticulum.[4]: 577 Mucous neck cells are located within gastric glands. These are shorter than their surface counterpart and contain lesser quantities of mucin granules in their apical surface.[4]: 578
The mucus produced by these cells is extremely important, as it prevents the stomach from digesting itself.[5]Parietal cells produce potenthydrochloric acid, which damages cells.Gastric chief cells produce pepsinogen, which is activated by the acid to formpepsin. Pepsin is a protease that can digest and damage stomach cells. To prevent these disastrous effects, mucus and bicarbonate ions (HCO3−) are secreted by the foveolar cells.
The mucus allows the acid at pH above 4 to penetrate lining, but below pH 4 (i.e. when acid is more concentrated) the acid cannot penetrate the mucus. This is called viscous fingering.[6] Thus the foveolar cells can pump out a lot of acid, but acid once in the lumen of the stomach is prevented from returning.
{{cite encyclopedia}}:|website= ignored (help)