Lecture 6 Flashcards
Paracrine Secretion
Secretion affecting neighboring cells
What is the difference between and exocrine gland and an endocrine gland?
Exocrine gland- epithelial outgrowths into underlying connective tissue that retain connection to overlying epithelium via one or more ducts
Endocrine gland- epithelial outgrowths into underlying connective tissue that lose connection to overlying epithelium (must secrete product into blood stream)
Autocrine Secretion
Secretion affects cell that released product
Simple Ducts
Ducts with no branching
Compound Ducts
Ducts with branching
Shapes of secretory portion?
Tubular
Acinar
Tubulo-alveolar
Types of secretion
Serous
Mucous
Mixed
Merocrine Secretion Mechanism
Serous secretion
No part of secretory cell is lost during secretion
Most glands (Pancreas, Salivary, Mammary)
Apocrine Secretion Mechanism
Apical cytoplasm is lost as part of secretion
Parts of apical membrane are lost around secretor product
Axillary sweat glands, Mammary glands
Holocrine Secretion Mechanism
Entire cell is lost during secretion
Cell has to decompose to release secretory product because it’s so large
Sebaceous glands
Structure of gland
Acinus, Intercalated duct, Striated duct, Intralobular duct, Interlobular duct, Interlobar duct, Lobar duct, Main duct
Lobule, Lobe, Capsule
Acinus
Secretory part of gland enclosed within basement membrane
Surrounded by myoepithelial cells
Intercalated duct
Squamous to low cuboidal
HCO3-/Cl- exchange
Striated duct
Cuboidal to columnar epithelium with basal striations
Striations represent accumulations of mitochondria for active transport
Interlobular duct
Pseudostratified columnar epithelium
