Physiology: salivary secretions

Question 1

What are the 2 catergories of salivary glands?

Answer 1

Extrinsic and intrinsic salivary glands

Question 2

Extrinsic salivary glands:
- Where are they located (relative to the oral cavity)
- What are they?
- Do they make the majority of saliva?

Answer 2

Outside oral cavity
Parotid, submandibular, sublingual
Yes - ~99%

Question 3

Intrinsic salivary glands
- Where are they located (relative to the oral cavity)
- What are they?
- How much saliva do they make?

Answer 3

Inside the oral cavity
Buccal glands, glands in the tongue
Very little - <1%

Question 4

What is the basic unit of a salivary gland?

Answer 4

Salivon

Question 5

What are the 2 secretory cell types?

Answer 5

Serous cells
Mucus cells

Question 6

Serous cells:
- What is contained in their secretions?

Answer 6

Watery
Enzymes (including alpha amylase)
Ions

Question 7

Mucus cells:
- What substance do they secrete?
- What is the main protein in this substance?

Answer 7

Mucus (duh :) )
Mucin

Question 8

Describe the saliva compision in the parotid, submandibular, sublingual, and buccal glands.

Answer 8

Question 9

Saliva:
- What are its 4 main components?

Answer 9

Water
Electrolytes
Digestive enzymes
Antimicrobial agents

Question 10

Saliva
- What % of it is water?
- What electrolytes does it contain?
- What digestive enzymes does it contain?
- What antimicrobial agents does it contain?

Answer 10

97-99%
Na, Cl, K, PO4, HCO3
Amylase, lipase, mucin
Antibodies, lysozyme, defensins

Question 11

Functions of saliva:
- Lubrication: by what protein?
- Digestion: by what protein?
- Protection: by what?

Answer 11

Mucin
Amylase
Saliva is slightly alkaline - protects teeth from acids

Question 12

Functions of saliva
- Control of water intake: how?
- Speech: how?
- Absorption: how?
- Taste sensation: how?

Answer 12

Dry mouth (less saliva) and increase thirst drive
Saliva enables tongue to move around the mouth
Saliva aids with sublingual absorption
Saliva dissolves chemicals, enabling them to interact with taste buds

Question 13

Salivons:
- What 2 ions go into the duct?
- What 2 ions go out of the duct?

Answer 13

K and HCO come in
Na and Cl go out

Question 14

When the rate of salivation increases:
- What happens to the transit time of fluid through the salivon?
- What happens to Na+ and Cl- concentration in the salivon?

Answer 14

Increases
Increases (less tiem for them to leak out into IF)

Question 15

Modulation of salivation by the ANS:
- What nuclei process salivation?
- Can higher brain centres modulate salivation?
- What effect does PNS and SNS have on salivation?
- What other factors can increase/decrease salivation?

Answer 15

Question 16

What is another name for excess salivation?
What drugs treat it?

Answer 16

Ptyalism/drooling
Low dose muscarinic receptor antagonists

Question 17

What is another name for insufficient salivation?
What drugs treat it?

Answer 17

Xerostomia
Low dose muscarinic receptor agonists

Question 18

Insufficient salivation
- Can trycyclic antidepressants and antimuscarnics cause it?
- Can radiotherpay cause it?
- Can dehyration, shock, renal failure cause it?

• Can it cause cavities, gum disease, bad breath?
• Can it cause constant thirst sensation?
• Can it alter taste?
• Can it impair chewing, swallowing and speech?

Answer 18

Yes to all