Wold 1 Flashcards
Parotid
Parotid (Stensen’s) duct opposite upper second molar
Serous gland; produces a watery (serous) secretion
Parotid;
Major source of
amylase
Submandibular
Submandibular (Wharton’s) duct opens
beneath the base of the tongue
Submandibular gland
Mixed (serous and mucous)
Submand. gland;
Secretions include
water/electrolytes and mucin
Active at rest
Sublingual
Lesser sublingual (Rivinus’s) ducts anterior floor Mostly mucous
Minor glands located throughout the oral cavity.
Labial Palatine Buccal Lingual (von Ebner’s gland) Sublingual mucosae
Minor salivary glands
Secrete mostly
mucous except von Ebner’s
Minor salivary glands
Contribute
5-10% of total saliva
Minor salivary glands
Harbor
lymphocytes
Von ebner’s gland
Secrete
lingual lipase
Initiates fatty acid digestion
Salivon
Acinus -Acinar cells (blind sac) --Serous Cells (enzymes) --Mucous Cells (mucin) ----**Myoepithelial Cells Intercalated Duct Striated Duct Excretory Duct
Composition of Saliva
WATER 99.5%
INORGANIC SALTS
Sodium, potassium, chloride, bicarbonate
Other components: calcium phosphate and magnesium sulfate
ORGANIC COMPONENTS
Acinar Cellular Origin
Amylase, Lipase, Mucoproteins, Proline-rich proteins, Tyrosine-rich proteins (and many others)
Nonacinar Cell Origin
Lysozyme, immunoglobulin, growth factors, regulatory peptides (NGF)
pH highly buffered 6.7 to 7.4
Nonacinar Cell Origin
Lysozyme, immunoglobulin, growth factors, regulatory peptides (NGF)
Acinar Cellular Origin
Amylase, Lipase, Mucoproteins, Proline-rich proteins, Tyrosine-rich proteins (and many others)
Salivary Fluid Secretion
-Intracellular Na+ kept low
-Intracellular K+ kept high
-Intracellular Cl- high
-In unstimulated cells, Ca2+ levels are low, and Ca2+ activated K+ and Cl- channels are closed.
=Upon stimulation, Ca2+ opens the Cl- and K+ channels.
Na+ leaks through tight junctions to follow Cl-
Primary secretion
(acini)
freely —- permeable
H2O
Secondary modification
Duct
H2O impermeable
Mechanisms of ductal modification
Number of transporters distributed in polarized manner across cell
Reabsorb Na+ and Cl- but NOT H2O
Slow flow rates allow more reabsorption
Primary secretions
Acinar region freely permeable to water
Electrolyte composition unaffected by flow rate
plasma like composition (isotonic)
Secondary secretions
Ductal region impermeable to water
Electrolyte composition strongly affected by flow rate
Low rate=high [K]; high rate=high [Na]
hypotonic
Mucin
Most abundant
protein in saliva
Mucin
Predominately produced by
sublingual & submandibular glands
Mucin
——- protein
carb rich