Page 614 - Atlas of Histology with Functional Correlations

Absorptive cells with microvilli covered by glycocalyx are most common in

intestinal epithelium
Goblet cells, interspersed between absorptive cells, increase in number
toward distal region
Enteroendocrine cells are scattered throughout the epithelium and intestinal
glands

Enteroendocrine cells are part of the diffuse neuroendocrine system (DNES)
Secretory granules of enteroendocrine cells located at the base of cells and
close to capillaries

Enteroendocrine cells secrete numerous regulatory hormones for the
digestive system
Undifferentiated cells in the base of intestinal glands replace worn-out
luminal cells
Paneth cells with pink eosinophilic granules in cytoplasm are located in the

intestinal glands
Paneth cells have defensive functions by producing the antibacterial enzyme
lysozyme and the hydrophobic peptide defensin

M cells are specialized cells that cover the lymphatic Peyer patches and are
part of the immune defense system

Glands of the Small Intestine

Intestinal glands located between villi throughout the small intestine
Intestinal glands open into the intestinal lumen at the base of the villi
Duodenal glands in the submucosa of duodenum are characteristic of this
region
Duodenal glands penetrate muscularis mucosae to discharge mucus and

bicarbonate secretions
Bicarbonate secretions enter base of intestinal glands and protect duodenum
from acidic chyme

Polypeptide urogastrone from enteroendocrine cells from the duodenal
glands inhibits hydrochloric acid secretions

Lymphatic Accumulations in the Small Intestine

Peyer patches are numerous aggregations of permanent lymphatic nodules
Peyer patches found primarily in the lamina propria and submucosa of the
terminal part of the ileum

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