EX3; Salivary Glands 1 Flashcards
Reduced salivation can cause what
increased incidence of caries
What two conditions have particularly potent hypo salivation effects
head and neck radiotherapy Sjogren’s syndrome
This is the injection of an isotope of Technetium, which binds to Na-K-Cl membrane transport system of acinar cells of salivary and other glands; used in the case study of the boy with no saliva
salivary gland scintigraphy
True or False genetic abnormalities of major salivary glands are fairly common
False; they are rare
True or False genetic abnormalities of major salivary glands may involve a single or multiple glands
True
What may salivary gland agenesis be accompanied by
other developmental disorders of the ectoderm or 1st branchial arch abnormalities of the hair, nails, missing teeth, or deafness
What is the severity of of salivary gland genesis dependent upon
the number of glands affected type of abnormality; total lack of gland vs hypofunction
What is important to do regarding salivary gland agenesis
early diagnosis and immediate measures to prevent caries
These are highly glycosylated glycoproteins that are viscous and responsible for lubricating the mucosal surface and providing a protective barrier
mucins
What do mucins tranp and clear
bacteria and sugar
This is secreted in saliva and serves an important function in buffering acids in the mouth (neutralization of acids and pH maintenance)
bicarbonate
These are calcium-binding proteins present in saliva; allowing saliva to be super saturated and contribute to enamel maturation and remineralization
proline-rich proteins statherin
These molecules contribute to the direct antimicrobial function os saliva (anti-bacterial, anti-fungal, anti-viral, etc.)
lysozyme peroxidase defensins histatins IgA
Some evidence suggests that saliva secretes this to actively participate in tissue repair
growth factors epidermal growth factor nerve growth factor
This provides lubrication that is critical to chewing and swallowing
mucins
Saliva contains these two enzymes which being to break down starch and fats into free fatty acids and glycerol
amylase = starch lipase = fats
Taste molecules must first be dissolved in this so they can be transported to the taste buds
water
Salivary glands are considered which type of glands
exocrine
How do salivary glands discharge their secretion
via a duct to an epithelial surface
What are the three major salivary glands
parotid submandibular sublingual
What is the normal daytime salivary flow rate
0.3-04 ml/min
What is the normal daytime volume of saliva in the mouth
0.8-1.1ml; most of it is a thin film that covers the teeth
This major salivary gland secretes a mixed but mostly mucous secretion and 7-8% of the total volume
sublingual
This major salivary gland secretes a serous (watery) saliva with amylase and around 60% of the total volume
parotid
This major salivary gland secretes a mixed but most serous saliva and 25% of the total volume
submandibuar
What are the minor salivary glands
Von Ebner glands labial palatal buccal lingual
What do the Von Ebner glands secrete (serous)
lingual lipases
What do the labial, palatal, buccla, and lingual glands secrete (mucous)
mucins
This salivary gland’s anterior end wraps around the caudal end of the mylohyoid and the duct travels superficially to empty into the oral cavity at Wharton’s duct
submandibular
This salivary gland is the largest and sits superficial to the caudal end of the masseter, and discharges saliva through Stenson’s duct
parotid
This salivary gland is the smallest and empties into a series of ducts behind Wharton’s duct called Bartholin and Rivinus ducts
sublingual
This serves as the supporting role of the salivary gland forming a capsule and organizing the gland into lobes
stroma
This serves as doing the characteristic work of the given gland; making saliva and discharging it to the final destination
parenchyma
The stroma is made up of what type of tissue
connective tissue
The parenchyma is make up of what type of tissue
epithelium
This divides the gland into lobes (large) and lobules (minor)
septa
This produces collagen in the stroma
fibroblasts
These supply the parenchyma in the stroma
blood vessels nerve fibers
This secretes antibodies in the stroma
plasma cells
This increases with age in the stroma
fat calls
During which embryonic week do the salivary glands begin development
6th
What is the order of gland development
parotid submandibular sublingual minor glands (2-3 months)
Where is the parenchyma of both the acini and ducts derived from
ectoderm (parotid) or endoderm
Where is the stroma derived from
neural crest
What are the two main components of the parenchyma
secretory portion called acini ducts
What are the acini composed of
individual acinar or secretary cells; they make saliva
What are the two main types of acinar cells
serous mucous
The acini open up into a series of what kind of ducts, which get progressively larger
intercalated started (secretory) excretory
The initiation of salivary gland development begins which what
the thickening of the ectoderm or endoderm forming a bud; signals exchanged between ectoderm/endoderm and mesenchyme
Once the salivary bud branches, what occurs
more branching then part of the branching hollows out in process known as cavitation
This molecule is important in cell adhesion, but disappears upon clefting/branching of the gland
e-cadherin
True or False The cell turns off its expression of e-cadherin, making way for branching to occur
False; it does not turn off the expression, it just re-directs it
This molecular is important for clefting to occur
BTBD7 (cleftin); siRNA’s were used to inhibit it
Cleftin is induced by what ECM molecule
fibronectin
What two actions does cleftin do
suppresses the expression of e-cadherin upregulates expression of snail2
What is the current hypothesis involving snail2
promotes change in cell shape, coupled with the loss of e-cadherin
True or False The acini secrete saliva
True
True or False The ducts only secrete saliva
False; they also resorb certain components
This is the primary secretion or primary saliva
water proteins and ions like Na and Cl
True or False the primary secretion/saliva is isotonic
True
True or False acinar cells are not water permeable, which duct cells are water permeable
False; acinar cells are water permeable duct cells are not
What does the duct cells secrete
few proteins like bicarbonate
True or False The secondary secretion/saliva is isotonic
False; it is hyoptonic
Salivary secretion is under what control
neural control; parasympathetics and sympathetics
Which cranial nerves play a role in salivary gland innervation
7 - facial 9 - glossopharyngeal
The sympathetic supply to the salivary glands originates where
in the IML of the spinal cord then to the superior cervical ganglion
The sympathetic nervous system is responsible for what kind of secretion
protein
Activation of the sympathetic nervous system along produces what
a protein-laden, viscous secretion that is not voluminous
The parasympathetic nervous system is mainly responsible for what kind of secretion
fluid secretion that account for most of the volume of saliva
In the salivary gland cells, this is maintained at high intracellular concentration with an energy-requiring ion pump
chloride
