Salivary Ducts

The lumen of the salivary acinus is continuous with that of a duct system that may have as many as three sequential segments. These are referred to as

• Intercalated duct, which leads from the acinus

• Striated duct, so-called because of the presence of "striatums," the infoldings of the basal plasma membrane of the columnar cells that form the duct

• Excretoiy ducts, which are the larger ducts that empty into the oral cavity

The degree of development of the intercalated ducts and striated ducts varies, depending on the nature of the acinar secretion (see Fig.15.22). Serous glands have well-developed intercalated ducts and striated ducts that modify the serous secretion by both absorption of specific components from the secretion and secretion of additional components to form the final product. Mucous glands, in which the secretion is not modified, have very poorly developed intercalated ducts that may not be recognizable in H&E sections. Moreover, they do not display striated ducts.

Intercalated ducts are located between a secretory acinus and a larger duct

Intercalated ducts are lined by low cuboidal epithelial cells that usually lack any distinctive feature to suggest a function

tf* ftSffe

0 0

Post a comment