Intestinal gland

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Intestinal gland
Small intestine low mag.jpg
Micrograph of the small intestine mucosa showing the crypts of Lieberkühn - bottom 1/3 of image. H&E stain.
Latinglandulae intestinales
Gray'ssubject #248 1174
 
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Intestinal gland
Small intestine low mag.jpg
Micrograph of the small intestine mucosa showing the crypts of Lieberkühn - bottom 1/3 of image. H&E stain.
Latinglandulae intestinales
Gray'ssubject #248 1174

In histology, an intestinal crypt (also crypt of Lieberkühn and intestinal gland) is a gland found in the epithelial lining of the small intestine and colon. The crypts and intestinal villi are covered by epithelium which contains two types of cells: goblet cells (secreting mucus) and enterocytes (absorbing water and electrolytes).

Structure[edit]

Intestinal crypts are found in the epithelia of the small intestine, namely the duodenum, jejunum and ileum. Intestinal crypts contain a base of replicating stem cells, Paneth cells of the innate immune system, and goblet cells, which produce mucous. [1] :282

Function[edit]

The enterocytes in the mucosa contain digestive enzymes that digest specific food while they are being absorbed through the epithelium. These enzymes include peptidases, sucrase, maltase, lactase and intestinal lipase. This is in contrast to the stomach where chief cells secrete pepsinogen, in the intestine the aforementioned digestive enzymes are not secreted by the cells of the intestine.

Also, new epithelium is formed here, which is important because the cells at this site are continuously worn away by the passing food. The basal (further from the intestinal lumen) portion of the crypt contains multipotent stem cells. During each mitosis, one of the two daughter cells remains in the crypt as a stem cell, while the other differentiates and migrates up the side of the crypt and eventually into the villus. Goblet cells are among the cells produced in this fashion. Many genes have been shown to be important for the differentiation of intestinal stem cells.[clarification needed]

Loss of proliferation control in the crypts is thought to lead to colorectal cancer.

Clinical relevance[edit]

Micrograph showing intestinal crypt branching, a histopathological finding of chronic colitides. H&E stain.

Pathologic processes that lead to crohn's, i.e. on-going, intestinal crypt destruction are associated with branching of the crypts.

Causes of crypt branching include:

Micrograph showing crypt inflammation. H&E stain.

Crypt inflammation is known as cryptitis and characterized by the presence of neutrophils between the enterocytes. A severe cryptitis may lead to a crypt abscess.

History[edit]

The eponymous term (crypts of Lieberkühn) is named after the 18th-century German anatomist Johann Nathanael Lieberkühn.

See also[edit]

Additional images[edit]

References[edit]

  1. ^ Deakin, Barbara Young ... [et al.] ; drawings by Philip J. (2006). Wheater's functional histology : a text and colour atlas (5th ed. ed.). [Edinburgh?]: Churchill Livingstone/Elsevier. ISBN 978-0-4430-6-8508. 

External links[edit]