2 Exo Panc and salivary gland [1] Flashcards
6 main constituents of saliva and their fxn
water HCO3 Mucin Amylase Lysozyme, lactoferrin, IgA Epidermal and nerve growth factors
Starch and fat digestion begins in the mouth with these two enzymes
amylase
lingual lipase
structure of salivary gland
Acini secrete fluid, electrolyte, enzymes
-bascially makes the saliva
Acini → intercalated duct → striated duct
Striated duct modifies the saliva
Myoepithelial cells of salivary gland↓
only found in salivary gland (not pancreatic)
- contractile muscle cells that facilitate secretion into acinus + intercalated ducts
Vomiting: need fast secretions
In saliva, as flow rate ↑s, NaCl reabsorption _____
↓s
no time to modify in striated ducts
More Na+ in Saliva (slightly hypotonic close to isotonic)
Rich in HCO3 (more secreted with faster flow)
In saliva, as flow rate ↓s, NaCl reabsorption _____
↑s
got time to adjust
lots of NaCl reabsorption - less NaCl in saliva
- HCO3- and K+ ions are secreted
Regulation of pancreatic secretions:
ACh is released from _____ nerves.
It stimulates the release of ______ enzymes from _____ cells
vagus and ENS
digestive enzymes, acinar cells
Regulation of pancreatic secretions:
Secretin is released from ______ cells in the ______ intestines in response to acid. It stimulates the release of ______ from ______ cells
endocrine cells
Proximal small intestines
a HCO3 rich soln from pancreatic duct cells
(the release of secretin is enhanced by CCK)
(it acts by increasing cAMP levels in the duct cells)
Regulation of pancreatic secretions:
CCK is released from _____ cells in the ________ in response to fats and proteins. It stimulates the release of ______ from ______ cells but has other effects in the duodenum
endocrine cells (like secretin) Proximal small intestines (like secretin) digestive enzymes from acinar cells (like ACh)
diff between Salivary and pancreatic secretion regulations
Salivary secretion is regulated by ANS
Pancreatic secretion is regulated by ANS and Hormones
Salivary acinus is very vascular. Increase in blood flow results in (pick one) concentrated/dilute saliva, that is modified by ____ cells
dilute
duct cells
- salivary ducts are fairly impermeable to water
which is more vascular, salivary acini or pancreatic acini?
salivary - responds to blood flow
pancreatic acini are not as vascular and respond to ACh and CCK
Ductal cells of the pancrease secrete what in response to secretin?
Water and Bicarb
salivary ducts are not very permeable to water
KHCO3 and NaHCO3 is rich in which juices, salivary or pancreatic?
KHCO3: saliva
(remember K+ and HCO3 are secreted with low flow into saliva)
NaHCO3: pancreas
Inactive proteases secreted by pancreas
Trypsinogen
Chymotrypsinogen
Proleastase
procarboxypeptidase
