Saliva

Question 1

genetic abnormalities of Major salivary glands

Answer 1

• rare
• single or multiple glands can be affected
• in isolation or as developmental abnormalities of the ectoderm or first branchial arch
• severity depends on glands involved and abnormalilty type (hypofunction vs. total lack of glands)

Question 2

what are the functions of saliva?

Answer 2

protection, buffering, tooth integrity, antimicrobial, tissue repair, digestion and taste

Question 3

what is the main component of saliva?

Answer 3

water

Question 4

mucins

Answer 4

highly glycosylated glycoproteins that are viscous and responsible for lubricating and providing a protective barrier - trap bacteria and sugar

Question 5

bicarbonate

Answer 5

in saliva to buffer acids in the mouth from bacteria or ingestion

Question 6

calcium-binding proteins

Answer 6

proline-rich and statherin that supersaturate saliva with calcium to help with enamel maturation and remineralization

Question 7

antimicrobial agents in saliva

Answer 7

lysozyme, peroxidase, defensins, histatins and IgA (anti-bac, fungal and viral)

Question 8

growth factors

Answer 8

help with tissue repair by wound healing and tissue growth

ex. epidermal growth factor and nerve growth factos

Question 9

digestion and saliva

Answer 9

lubricates (mucins) and enzymes like amylase and lipase that breakdown food

Question 10

taste

Answer 10

tasty molcules first need to be dissolved in water to transport to taste buds

Question 11

what type of glands are salivary glands?

Answer 11

-exocrine

Question 12

in the absence of stimualtion, what are the normal salivary rates?

Answer 12

0.3-0.4 ml/min and the volume of saliva in the mouth is .8 to 1.1 ml (to coat the oral surfaces)

Question 13

saliva flow during sleep

Answer 13

flow rates decrease!

Question 14

major salivary glands

Answer 14

parotid (60%), submand (25%), subling and minor (7-8%)

Question 15

serous or mucous: parotid?

Answer 15

Seroud

Question 16

S or M: submand?

Answer 16

mixed

Question 17

S or M: subling?

Answer 17

mixed

Question 18

S or M: von ebner?

Answer 18

s, source of the lingual lipase (breaks fat)

Question 19

S or M? other minor glands?

Answer 19

pure mucous (major source of mucins)

Question 20

parotid gland duct

Answer 20

stensons (opposite 2nd molar)

Question 21

submandibular duct

Answer 21

whartons on the lingual frenum (wraps around mylohyoud mm.)

Question 22

subling duct

Answer 22

a series of ducts in the sublingual fold behind whartons

**called bartholins and rivinus ducts

Question 23

salivary gland basic structure

Answer 23

parenchyma and stroma
-stroma is CT and parenchyma is epithelium
stroma is supportive (septa and capsule) and parenchyma make and secrete the saliva

Question 24

stroma

Answer 24

• made of septa and capsule
• contains fibroblasts that make collagen, nerve and vessels that got o parenchyma, plasma cells (mainly IgG), and fat cells that increase with increasing age

Question 25

parenchyma

Answer 25

2 main components: secretory portion (acini) and ducts

Question 26

how many types of acinar cells?

Answer 26

2 - make three types of secretory endpieces (serous, mucous and mixed) empty into ducts that get progressively larger

Question 27

gland development (time frame)

Answer 27

begins in the 6th week IU (parotid first, then submand later in 6th wk, then subling and minor glands btwn the 2nd and 3rd mo IU

Question 28

parenchyma origin

Answer 28

epithelium so either ectoderm or endoderm | parotid - ecto, submand - endo or ecto and minor - endo

Question 29

stroma origin

Answer 29

neural crest

Question 30

actual process of salivary gland development

Answer 30

-protrusion thickened epi cells into mesenchyme, bud forms, e-m interactions, branching and hollowing out (like branched structures such as mammary glands, lung etc..)

Question 31

E-cadherin

Answer 31

an important cell-adhesion molecule involved in branching - disappear in cleft or branching but apparent on other parts of the cell * *redirecting expression in the cells of e-cadherin

Question 32

Cleftin

Answer 32

supresses the action of E-cadherin and upregulates snail-2 * *snail-2 changes cell shape * *e-cadherin loss and snail-2 upregulation induces gap formation

Question 33

how is cleftin expressed?

Answer 33

induced by fibronectin cells in the ECM

Question 34

primary vs. secondary salivary secretion

Answer 34

primary is water with proteins, ions and Na and Cl and is isotonic secondary saliva is hypotonic because the duct cells resorb Na and Cl but secret proteins and bicarbonate ion

Question 35

are acinar cells of duct cells water permeable?

Answer 35

acinar

Question 36

innervation of the salivary glands

Answer 36

under neuronal control (symp and pararsymp)

Question 37

parasym innervation

Answer 37

pre-gang in brainstem, begin in salivatory nucleus, go down CN Vii and IX and synapse on post-gang neurons near each of the glands

Question 38

symp innervation

Answer 38

orginate in cell bodies in the IML of spinal cord, synapse in superior cervical ganglion and post-gang in SCG supply the glands

Question 39

sympathetic secretion

Answer 39

- responsible for protein secretion, post-gang release NE, binds to beta-adrenergic recpetors in acinar cells. GCRP coupled to AC that upregulates CAMP, that activates PKA, which phosphorylates secreotry granules that have proteins that are released * *protein laden, viscous secretion, NOT voluminous

Question 40

parasym secretion

Answer 40

fluid secretion, volume of saliva - psot-gan releases Ach, binds to muscarinic receptor on acinar cell (a GCPR), but its cples to Phosholipase C, which liberates IP3, liberating Calcium from the ER, which opens Cl-channels in the lumen that creates an osmotic gradient that draws sodium and water * *Cl maintained at high concentration intracellulary through and energy ion pump

Question 41

generalized acini

Answer 41

cluster of acini cells surrounding a central lumen. cells are held togehter by tight junctions with intercellular spaces. intercellular spaces allow water and ions, but restrict larger molecules. The end of the acinar cell that faces the lumen contains secretory granules. Also contains myoepithelial cells. entire endpiece is surrounded by basal lamina

Question 42

serous (acinar) cell

Answer 42

- pyramidal shape - rest on the basal lamina - short, irregular microvilli at the basal end to increae SA - polarized, protein secreting (protein machinery like RER and golgi well-defined) - secrete many enzymes and glycoproteins

Question 43

mucous cell

Answer 43

- cubodal/columnar - oval nuclei pressed towards the base (not round) - arranged in tubules around larger central lumen, secrete ALOT of mucins - secretory granules are pale staining because of mucins biochemical characteristics

Question 44

serous demilume

Answer 44

mucus acinus topped with serous cells | **artifact

Question 45

rapid freeze fixation

Answer 45

gets rid of serous demilume and sqwuished nuclei

Question 46

myoepithelial cells

Answer 46

- epithelial and contractile properties - neurally innervated - facilitate saliva movement into the ductal system - wrap around acini and ducts

Question 47

3 tpes of ducts

Answer 47

intercalated, striated (secretory) and excretory (collecting)

Question 48

what type of duct is missing in minor salivary glands?

Answer 48

striated (intercalated to many excretory ducts)

Question 49

intercalated

Answer 49

-cubodal cells, short, several acini to one intercalated duct, smallest duct, centrally placed nuclei, secretes a few antimicrobial proteins (lysozome and lactoferrin) main purpose: convery saliva

Question 50

striated duct

Answer 50

intercalated lead to striated, longer, more active, SITE OF RESORPTION (responsible for hypotonic saliva), secrete proteins (kalikren) and BICARB (buffer), tall columnar cells, highly polar, short microvilli on apical end but there basal end has MANY INFOLDINGS OF TEH BASOLAT MEMBRANE - STRIATED, large SA for resorption, many mitochondira

Question 51

is the resorption in the striated duct need energy?

Answer 51

YES (atp is critical)

Question 52

travel of the Na and Cl in the striated ducts

Answer 52

from the lumen through the apex to the basal infoldings to adj. capillaries **ENERGY

Question 53

excretory duct

Answer 53

* *PRIMARY PURPOSE IT TO CARRY SALIVA TO ORAL CAV - no secretion or absoprtion - get progresively wider as they get to oral cav - goes from single epi layer to pseudostrat epith (maybe strat and kerat) as the oral epithelium is reached - irregular positioned nuclei - exec duct in stroma of CT (so fibroblasts surround) - goblet cells mingle with exec duct and secrete mucins

Question 54

what are the exceptions to the S/M rule for minor salivary glands

Answer 54

blandin and nun on the anterior tongue are mixed and von ebners on post tongue are serous

Question 55

saliva with age

Answer 55

-loss of parenchyma tissue and reduced salivary flow (medications)

Question 56

mumps

Answer 56

affect parotid gland, obstuction of ducts through calcified stones (whartons duct) or mucous plugs (minor glands)

Question 57

saliva and viruses

Answer 57

viruses can replicate in salivary gland and shed into saliva

Question 58

xerostomia

Answer 58

feeling of dry mouth

Question 59

what is affected by radiation?

Answer 59

intitally gland function and then cell death (acinar cells) | **try to treat the salivary site

Question 60

what type of taste beat at activating salivary flow?

Answer 60

tart

Question 61

chewing gum activates?

Answer 61

PDL - increaes saliva