Glands are organized arrangements of secretory cells. All exocrine glands (and also most endocrine glands), are composed of epithelial tissue. Although most glands give the appearance of being "solid" tissue, their epithelial nature is expressed by the organization of secretory cells into tubules, acini, or cords. Every exocrine secretory cell has some portion of its plasma membrane exposed to an external surface, communicating with the outside of the body by a system of ducts. Show Histologically, glands are described using some standard vocabulary, with which you should be familiar. Serous / Mucous / Mixed The serous / mucous distinction is based on the secretory cell's product -- whether it is a clear, watery solution of enzymes (serous, like serum) or else a glycoprotein mixture (mucous, like mucin). These two categories of secretory products come from two distinct categories of cells, each with a characteristic appearance. Simple / Compound
Acinus / Tubule / Cord
Endocrine / Exocrine
Intercalated / Striated Ducts
Parenchyma / Stroma
Gastric Glands Gastric glands are the simple tubular mucosal glands of the stomach. These glands consist predominantly of parietal cells which secrete acid and serous chief cells which secrete gastric enzymes. Pancreas Functionally, the pancreas has two more-or-less independent roles.Structurally, the pancreas is a compound, acinar, serous, exocrine gland with scattered islets of endocrine tissue. If you're familiar with basic gland terminology, little else needs to be said.In pancreatitis, the appearance of the pancreas may be altered by inflammatory infiltrate in the stroma. In acute pancreatitis, release of pancreatic enzymes can cause proteolytic digestion and associated haemorhagic necrosis. Chronic pancreatitis can lead to atrophy and fibrosis of the parenchyma. For print images, see Milikowski & Berman's Color Atlas of Basic Histopathology, pp. 304-306.
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