Physiology of saliva Flashcards
What is an exocrine gland?
gland that secretes substances on epithelial surface in by way of a duct
What type of gland is a salivary gland?
exocrine gland
What two efferent nerves work collaboratively in reflex of salivary secretion?
sympathetic and parasympathetic
What glands does the parasympathetic and sympathetic not work together?
minor mucous glands
Efferent pathway
Parasympathetic; Salivary Nuclei signals which glands?
parotid + sublingual
Efferent pathway
Sympathetic: Thoracic spinal cord signals which glands?
parotid + submandibular
Where do negative signals come from?
CNS
e.g if feel anxious mouth will go dry
Autonomic nerve fibres supply which structures in the salivary gland?
Acinus
Blood vessel
duct
What does the sympathetic nerves secrete?
proteins
Do parasympathetic nerves cause vasodilatation or vasoconstriction?
vasodilatation
What is vasodilatation and vasoconstriction?
Vasodilatation - widening blood vessels
Vasoconstriction - narrowing blood vessels
What do the parasympathetic nerves secrete?
most fluid and some protein
What do sympathetic nerves contract?
myoepithelial cells
What is sympathetic nerve neurotransmitter?
Noradrenaline
What is parasympathetic nerve neurotransmitter?
Acetylcholine
Where does stage one of protein and water (NaCl) being secreted occur?
Acinus
Where does stage two of NaCl being released occur?
Striated Duct
What do sympathetic nerves release in minor glands?
neuropeptides
What does acetylcholine muscarinic receptor (a-adrenergic) Atropine reduce?
Fluid secretion
What does B-adrenergic or VIP propranolol reduce?
protein secretion
Salivary gland fluid secretion is dependent upon a gradient in concentration of ……….
sodium
Sodium potassium ATPase
What does sodium ATPASE pump out extracelluar
K+
What does sodium ATPASE pump out intracellular
Na+
Salivary secretion is dependent upon opening of apical …….. channels up stimulation of ……… cell
chloride
acinar
What does the parotid, sublingual and submandibular glands secrete?
serous (very fluid almost no mucin)
seromucous (sticky with mucin)
mucous (sticky with lots of mucin)
What is the saliva in the acini? (stage one)
Isotonic
What is the saliva in the duct? (stage two)
Hypotonic
Key event in activating fluid secretion
Signal from acetylcholine binds to muscarinic receptor, gives rise to Ca2+ (increases) - KICKS OFF secretory process, opens Cl channel
