Mouth/Salivary Glands

Question 1

parotid gland secretion (general)

Answer 1

rich in serous cells for secreting watery (Serous) secretion containing carbo digestive enzyme (amylase)

Question 2

submandibular and sublingual secretions (general)

Answer 2

mucus secreting cells for secretion of a more viscous mucoprotein-rich secretion

Question 3

salivons

Answer 3

units that collectively make up a salivary gland

Question 4

what each salivon consists of…

Answer 4

an acinus (end piece)

and 2-component duct system

• the intercalated duct
• large diameter, striated appearing collecting duct

Question 5

myoepithelial cells

Answer 5

line the acinus on its blood side

designed for contraction that can enhance the rate of fluid movement from the acinus through the ducts and into the mouth

Question 6

function of saliva

Answer 6

1. defense
   - mouth cleansing
   - antibacterial action
   - neutralization of gastric reflux
2. solvation
   - facilitates taste
3. lubrication
   - forms small food particles
   - forms bolus
   - aids in speech
4. digestion
   - initiates starch and lipid digestion
   - initiates responses in more distal
   - GI tract

Question 7

mucus and water defense function in saliva

Answer 7

lubrication against mechanical trauma

dilution of chemical components

bolus temperature control

oral hygiene

Question 8

HCO3- defense function in saliva

Answer 8

neutralizes acid in food

neutralizes HCl refluxed from stomach

antibacterial, neutralizes bacterial acid

Question 9

lactoferrin and muramidase defense function in saliva

Answer 9

antibacterial: binds iron
antibacterial: hydrolyzes cell walls

Question 10

EGF defense function in saliva

Answer 10

cell growth and repair

Question 11

water and mucus digestive function in saliva

Answer 11

lubrication of bolus

Question 12

alpha amylase digestive function in saliva

Answer 12

starch digestion (optinum pH 7)

Question 13

lingual lipase digestive function in saliva

Answer 13

fat digestion (acidic pH)

Question 14

R protein function in saliva

Answer 14

binds B12 –> pancreatic protease removes R protein from B12 complex….facilitates binding of B12 to intrinsic factor

Question 15

kallikrein

Answer 15

increases blood flow to salivary glands

…by conversion of plasma kininogen to bradykinin

Question 16

fluid entering the acinus has a similar electrolyte profile as what?

Answer 16

blood

Question 17

as the acinar fluid progresses down the ducts…

Answer 17

it is acted upon ductular cells in a way that cahnges its electrolyte and osmolar composition

end results –> secretion entering the mouth is more hypo-osmolar and richer in K+ and HCO3- than acinar fluid

Question 18

how does HCO3- enter the lumen of the acinus

Answer 18

HCO3-/Cl- cotransporter in apical membrane

Question 19

how does K+ enter the acinus lumen

Answer 19

K+ channel in apical membrane

Question 20

how does Na+ enter the acinus lumen

Answer 20

mostly through paracellular diffusion across the tight junctions

Question 21

transporters in basolateral acinus cell membrane

Answer 21

Na+/H+ exchanger

Na/K pump

K+ channels out –> to keep gradient for pump

Na+/2Cl-/K+ cotransporter into cell

Question 22

primary acinus secretion

Answer 22

amylase

isotonic for Na+, K+, Cl-

Question 23

modified secretion of the primary acinus secretion

Answer 23

Na+, Cl- absorbed

K+, HCO3- secreted

Question 24

apical membranes of ductular cells are impermeable to what

Answer 24

water –> how fluid becomes more hypo-osmolar than acinus fluid

Question 25

NaCl absorption in ductular cells apical membranes

Answer 25

Na/H exchanger (H out) Na channels

Question 26

transporters in ductular basolateral membrane

Answer 26

Na/K pump K+ channel out Cl- channel out Na/H exchanger (H out)

Question 27

K+HCO3- secretion in ductular apical cell membrane

Answer 27

Cl-/HCO3- exchanger K+ exchanger (with another proton?)

Question 28

mediators of salivary secretion

Answer 28

NO hormones all neural inputs...can be activated before food enters mouth....but get most when food in mouth due to chemo and pressure receptors activation upon chewing

Question 29

characteristic of a sympathetic salivary secretion a. salivary output b. duration of flow c. composition d. 2nd messenger e. gland denervation results in...

Answer 29

a. scant increase b. transient c. mucoprotein rich (thick) d. cAMP e. without atrophy

Question 30

characteristics of parasympathetic salivary secretion a. salivary output b. duration of flow c. composition d. 2nd messenger e. gland denervation results in...

Answer 30

a. copious b. ?? c. protein poor, watery d. Ca2+ e. atrophy over time - since increases blood flow to galnd

Question 31

sympathetic innervation (adrenergic) to glands

Answer 31

T1-T2 --> superior cervical ganglion --> submandibular and sublingual gland

Question 32

parasympathetic innervation (cholinergic) to glands

Answer 32

medulla oblongata (superior or inferior salivary nuclei) superior SN --> CN VII (facial) --> submandibular g. --> submandibular/sublingual inferior SN --> CN IX (glossopharyngeal) --> otic ganglion --> parotid gland

Question 33

cellular response to NE (sympathetic)

Answer 33

release of intracellular cAMP drives the release of protein adn amylase

Question 34

cellular response to Ach (parasympathetic)

Answer 34

release of intracellular Ca2+ yields the fluid rich acinar secretion

Question 35

cell response to substance P (parasympathetic)

Answer 35

same effect as Ach - but not as strong