Lecture 1.B. - Salivary Secretions Flashcards
Salivary secretions total an average of ___L per day, which accounts for about 1/3 of _____ volume, or 7% of _______ fluid.
1L per day
1/3 of Plasma Vol
7% of Extracellular Fluid
The salivary glands receive a large blood supply from branches of the ____ artery that innervate the sub____ gland, sub______ gland, and ______ gland.
Carotid artery
Sublingual gland
Submandibular gland
Parotid gland
Concentration of Na+, HCO3-, and Cl- in saliva all _______ (increase or decrease?) with increased flow.
So patients undergoing chemo who suffer from Xerostomia will have ______ (basic or acidic?) saliva.
______ is a free-radical scavenger used in the prevention of Xerostomia.
Patients with impaired salivary glands can also be treated with ______ or ________, which are salivary substitutes.
Increase
Acidic
Amifostine
Xyletol
Carboxymethylcellulose
While K+ and HCO3- tend to be at ______ (lesser or greater?) concentrations in the saliva vs in plasma, Na+ and Cl- are always at ______ (lesser or greater?) concentration.
Initially, secretions at the base of the salivary gland (by the acinar cells) are ______ (hypo-, hyper-, or isotonic?) to plasma. As the secretions travel through the gland into the oral cavity, _____ and _____ are absorbed via ____ cells.
How does flow rate affect absorption of these ions?
Greater
Lesser
Isotonic
Na+
Cl-
Duct
Higher flow rate –> less Na+ and Cl- absorbed.
_____ is secreted into salivary glands, unlike Na+ and Cl-, which are absorbed.
How does flow rate affect its concentration?
HCO3-
Higher flow rate –> more secreted into gland, so higher concentration in saliva. At very low flow rates, HCO3- concentration in saliva can become less than in plasma, making saliva acidic.
On the apical side of Acinar cells, ____ is exchanged for HCO3-, ____ is exchanged for H+, and ____ is also exchanged for H+ (but in the opposite direction.)
Which ions come into and which go out of the Acinar cells on the apical side?
Cl-
Na+
K+
Na+, K+, and Cl- come in, while HCO3- goes out.
On the lumenal side, ____ exits the Acinar cell via a channel, ____ comes in via a channel, and Na+ is PUMPED out via the ______ ATPase (which of course means 2K+ come in for every 3Na+ that get pumped out per ATP).
Cl-
K+
Na+/K+ ATPase
Acinar cells secrete organic material comprised of Antimicrobial peptides which include ____ and ____, Proline-rich peptides that help with _____ maintenance, and Mucus for lubrication.
Defensins and Histatins
Enamel maintenance
__-_____ is an enzyme secreted by Acinar cells that digests starch. Its activity is ____ (increased or reduced?) in the stomach.
____ ____ is an enzyme secreted by Acinar cells that hydrolizes triglycerides. While its optimal pH is ____, it is pH stable, so its activity continues in the stomach and proximal intestine. Note this enzyme can catalyze lipolysis reactions without ____ ____.
Alpha-amylase
Reduced
Lingual Lipase
5
Bile Salts
It is important to remember BOTH the PNS and SNS STIMULATE salivary secretion, though the _____ is the main regulator.
PNS
Autonomic control of salivary secretions is as follows:
Stimulus –> Neurons in Salivary nucleus of the _____ –> PNS via cranial nerves ___ and ___ –> ACh binds ____ receptor on salivary gland cells and acts via ____ pathway to increase intracellular Ca++ –> Increases secretion, myoepithelial cell contraction, vasodilation, metabolism and growth.
Medulla
IX and VII
M3
IP3
Sympathetic innervation of salivary glands comes from the _____ _____ ganglion.
Superior Cervical
