Lecture 7: Epithelial glands Flashcards
Exocrine glands
The epithelial down growth may remain connected to the epithelial layer from which it originated
Endocrine glands
The epithelial down growth may degenerate, leaving the secretory tissue isolated from its parent epithelial layer
Paracrine
Secretion affects neighboring cells
i.e. growth factor
Autocrine
Secretion affects the cell that released the secretory product
i.e. IL-2 secreted by T cells
____ ______ glands do not exhibit ductal branching
simple multicellular
___ ______ glands have ductal branching
compound multicellular
Shapes of secretory portion of glands
Tubular (straight, coiled and branched)
Alveolar
Tubuloalveolar
Types of simple multicellular glands
Tubular
Coiled
Tubular branched
Acinar/alveolar
Types of compound (branched) multicellular glands
Branched tubular
Branched alveolar
Branched tubulaveolar
Types of secretion
Serous (parotid)
Mucous
Mixed (serous-mucous) (submandibular, sublingual)
Merocrine gland
Secretory product is stored in membrane bound vesicles, cytoplasm is retrieved in exocytosis/endocytosis cycle
Apocrine gland
Apical cytoplasm is released with secretory product (axillary sweat glands)
Holocrine gland
Entire cell is released as part of secretory product (sebaceous glands)
Compound gland is a multicellular gland divided into
Subunits called lobules (each lobule is equivalent to a simple branched gland)
Parenchyma
Highly cellular. The components of the gland derived from epithelium (secretory units and ducts) comprise the parenchyma
Stroma
Less cellular. Connective tissue capsule surrounding entire gland as well as the CT partitions separating the lobules
Connective tissue partitions separating lobes and lobules are called
Septa or trabeculae. Interlobar septae and interlobular septae, respectively.
Lobe
Subdivision of a compound gland separated from adjacent lobes by septae
Lobule
Subdivision of a lobe separated by delicate septae.
Acinus (acini) are the ? Secretion can be? Outer surface is surrounded by?
Secretory components of a lobule. Can be serous, mucous or mixed. Outer surface surrounded by basement membrane
Myoepithelial cells are found where
Found between basement membrane and the secretory cells of the acinus
Myoepithelial cell function and characteristic
Derived from epithelium, characterized by extensive actin bundles resulting in contractility
Intralobular duct location and types
Ducts that lie within a lobule
Intercalated or striated
Intercalated duct function and epithelial type
Drain the secretory acini, involved in bicarbonate/chloride ion exchange. lined by low cuboidal epithelium
Striated duct function and epithelial typle
Line by cuboidal–>columnar epithelium with basal striations for active transport. Actively absorb sodium/secrete potassium
Interlobular ducts formation/location/epithelial cell type
Formed by confluence of two or more striated ducts, found in septae between adjacent lobules.
Pseudostratified columnar
Intralobar ducts formation/epithelial cell type
Formed by confluence of two or more interlobular ducts
Lined with columnar–>stratified columnar epithelium
