salivation

Question 1

difference between extrinsic and intrinsic salivary glands

Answer 1

extrinsic- not found in oral cavity (use ducts)
intrinsic- found in oral cavity

Question 2

extrinsic salivary glands (90%)

Answer 2

parotid
submandibular
sublingual

Question 3

intrinsic salivary glands (10%)

Answer 3

buccal
labial
palatine

Question 4

types of cells in extrinsic salivary glands

Answer 4

parotid - serous
submandibular- serous and mucous
sublingual - primarily mucous, some serous

Question 5

types of cells in intrinsic salivary glands

Answer 5

primarily mucous cells

Question 6

where does the parotid gland empty

Answer 6

empties via the parotid duct into the 2nd maxillary molar

Question 7

where does the submandibular gland empty

Answer 7

empties via wharton duct to the lingual frenulum

Question 8

where does the sublingual gland empty

Answer 8

has 10-20 ducts, empties on floor of the mouth

Question 9

what nerve innervates the submandibular and sublingual glands

Answer 9

facial nerve(CN VII), coming from the superior salivatory nucleus. exits skull through internal acoustic meautus

Question 10

what nerve innervates the parotid gland

Answer 10

glossopharyngeal nerve(CN IX), from the inferior salivatory nucleus. exits skull through jugular foramen

Question 11

what receptors in the oral cavity stimulate saliva production

Answer 11

chemoreceptors (e.g. acidity)
mechanoreceptors (e.g. chewing)

Question 12

what pathway do CNVII and CNIX increase salivary volume by?

Answer 12

parasympathetic pathway

Question 13

how does the sympathetic nervous system effect the extrinsic glands

Answer 13

via the superior cervical ganglion (SCG) originating from T1-T4, makes thicker protein-rich saliva

Question 14

what does the parasympathetic nervous system primarily secrete?

Answer 14

acetylcholine

Question 15

what does the sympathetic nervous system primarily secrete?

Answer 15

noradrenaline

Question 16

how does water enter the acinus of the gland?

Answer 16

through aquaporin V across apical membrane
through paracellular transport
through aquaporin III on the basolateral membrane into acinar cells, then aquaporin V

Question 17

how does sodium enter the duct

Answer 17

paracellular transport between acinar cells

Question 18

how does potassium enter the duct

Answer 18

potassium-hydrogen pumps
through potassium leakage channels

Question 19

how do chloride ions enter the duct

Answer 19

CFTR proteins

Question 20

how do bicarbonate ions enter the duct

Answer 20

when calcium and water combine in the presence of carbonic anhydrase bicarbonate ions formed, bicarbonate enters and some chloride may leave

Question 21

what are the amounts of chloride and sodium ions pulled into the duct equal to

Answer 21

the amount of water in the duct - acinus is isotonic to blood plasma

Question 22

what is the secondary secretion in relation to the blood plasma

Answer 22

hypotonic - sodium and chloride ions re-enter acinar cells, so less solutes

Question 23

acetylcholines effect

Answer 23

binds to M3 receptor
stimulates Gq protein, binds to GTP
stimulates PLC enzyme
this breaks down PIP2 into DAG and IP3
IP3 stimulates an increase in calcium levels
DAG activates protein kinase C
calcium activates CAM kinases to phosphorylase channels, increasing secretion of substances into the acinate

Question 24

noradrenaline effect on glands

Answer 24

binds to beta receptors on acinar cells
activates Gs protein, which is bound to GTP
stimulates an effector enzyme on the cell membrane - adenyl cyclase converts ATP to cAMP
cAMP activates protein kinase A
protein kinase A stimulates exocytosis of granules
releases mucin and salivary amylase (increasing protein content)
can also cause vasoconstriction, deceasing electrolyte and water secretions from the blood

Question 25

overall functions of saliva

Answer 25

oral hygiene
antimicrobial
chemical digestion
hydrate the oral cavity
increase taste of substances
decreases incidence of cavities

Question 26

what antimicrobial substances does saliva contain

Answer 26

IgA antibodies
cystatins
histatins
lysozymes
proline rich proteins