Oral Environment 2 Flashcards
What are the 13 main salivary proteins?
Amylase
Cystatin
Gustin
Histatin
Immunoglobins
Lactoferrin
Lactoperoxidase
Lipase
Lysozyme
Mucoproteins
Plasma proteins
Proline-rich proteins
Statherins
What is amylase?
Enzyme,
activated by Cl–,
requires Ca+
Hydrolyses 1-4 starch alpha glycosidic links into maltose, maltriose, alpha-limit dextrins
What does lysozyme do?
non-specific defence
Attacks bonds in bacterial cell walls, causing lysis
What does lactoperoxidase do?
Enzyme from salivary glands and some bacteria
antibacterial action from oxidation of thiocyanate
What do cystatins do?
Inhibit cysteine proteases, especially in bacteria
Antimicrobial function
What does gustin do (carbonic anhydrase 4)?
Zinc-containing protein
Reported to facilitate taste function by activating taste buds
What are histatins?
Histidine-rich proteins
Inhibit CaPO4 precipitation (precipitation allows remineralisation)
Antimicrobial
What do immunoglobins do?
From plasma cells in salivary glands
Secretory IgA
Confers specific immunity against bacteria
What is lactoferrin?
Binds Fe 3+
Antibacterial -especially against bacteria that require Fe
What is lipase?
From von Ebner glands on tongue
Lingual lipase
Hydrolyses triglycerides
What are mucoproteins (mucins)?
CHO-protein macromolecules
Bind to tooth and epithelial surfaces:
Protective role
Lubrication
Component of primary pellicle
Affects bacterial adhesion
Promotes bacterial aggregation easier clearance from mouth
What do proline rich proteins do?
Inhibit growth of Ca3PO4 crystals
Anticalculus effect
Adsorb on to hydroxyapatite:
Acts as diffusion barrier
Decreases mineral loss
Resists acid attack
Allows remineralisation
Regulates bacterial attachment
What do statherins do?
Prevent precipitation of Ca3PO4 from saliva
Anticalculus action
What are examples of unconditioned salivary stimuli?
Mechanical
pressure on PDL / oral mucosa
Chemical
gustation
olfaction
common chemical sense
What does chewing (pressure on PDL) cause?
increased flow in the glands where chewing is happening (left or right)
Describe gustation stimuli
receptors on taste buds:
tongue dorsum, palate and epiglottis
different potencies
acid > umami = salt > sweet > bitter
adaptation to constant stimulus
Is olfactory a strong stimuli?
no, very weak
What is common chemical stimuli?
a ‘primitive’ response to irritants, injury
mediated by nociceptors in mucous membranes
contributes to the ‘taste’ of spices
What are conditioned salivary stimuli?
psychic (thinking)
visual
auditory
think pavlovs dog
What is the parasympathetic control of salivation?
increased secretion
vasodilation
serous watery
What is the sympathetic control of salivation?
increased secretion
vasoconstriction
mucous protein thick
How many stages in saliva production?
2
Where does primary saliva stage occur?
acinus
Where does secondary saliva stage occur?
duct
What happens in primary stage
ACh attaches and causes influx of Cl- which enters the lumen
Na+ and water also enter the lumen creating sodium chloride and water
Bicarbonate is also increased via carbonic anhydrase
Is salivary secretion mostly parasympathetic or sympathetic?
parasympathetic
What happens in secondary stage?
Na+ and Cl- are reabsorbed
K+ and bicarbonate are secreted
What pH is saliva?
6.8
What kind of solution is saliva?
hypotonic
Which salivary protein facilitates taste function by activating taste buds?
Gustin
Which salivary protein is a potent PDE 5 activator? (PDE 5 is main target for all drugs that treat erectile dysfunction - side effect can be change of taste)
Gustin
What 2 diseases does histatins in saliva inhibit?
- Candida albicans - fungus that is naturally present in mouth, can eventually take control of mouth if out of control
- Streptococcus mutans - causes caries, has different subtypes and thrives in acidic conditions
