Lecture 42 - The Pancreas Flashcards
fat is assimilated into ____ for delivery to ____
micelle; small intestine
what are the functions of the pancreas
- endocrine
- exocrine
- secretion of water, Na+, HCO3-, and Cl-
what hormones are produced by the pancreas
1 insulin
2. glucagon
3. somatostatin
4. pancreatic polypeptide
what are the exocrine products of the pancreas
digestive enzymes
what is the anatomy of the pancreas
lobulated, thin, elongated organ
how are pancreatic enzymes delivered to the GI tract
through duct system ( [accessory] pancreatic duct) and opening into major/minor papilla
T/F: the pacreatic duct is most important in cats whereas the accessory duct is most important in dogs
TRUE
describe the pancreatic duct in cats and what their specific anatomy predisposes them to
duct fuses with common bile duct before entering the duodenum which predisposes them to inflammatory disease of the intestine, pancreas, and biliary tree (triaditis)
what is the consequence of pancreatitis in the:
duodenum
intestinal inflammation, melena, V+
what is the consequence of pancreatitis in the:
greater curvature
V+, gastric ulcers, hematemesis
what is the consequence of pancreatitis in the:
transverse colon
large bowel D+, hematochezia
what is the consequence of pancreatitis in the:
peritoneum
abdominal pain, effusion
what is the consequence of pancreatitis in the:
liver/common bile duct
hepatocellular damage, stasis of bile
what is the histology of the pancreas
- Islet of Langerhans (polygonal cells)
- Acini
what produces insulin? what is the action?
beta cells
lower blood glucose
what produces glucagon? what is the action?
alpha cells
increase blood glucose
what produces somatostatin? what is the action?
D cells
inhibit secretions
what produces pancreatic polypeptide? what is the action?
F cells
reduce secretions and appetite
acinar cells do what
produce enzymes
stimulated by CCK and acetylcholine
what activates all digestive enzymes
trypsin
T/F: digestive enzymes are synthesized and secreted as inactive precursors
TRUE
T/F: the pancreas makes enzymes that only diagnose protein and fats
FALSE - all diet components
in exocrine pancreatic insufficiency, the trypson-like immunoreactivity test is ____
decreased
pancreatitis can be indicated by ____ lipase
increased
what converts trypsinogen to trypsin
enteropeptidase
pancreatic enzymes are digested ____, while brush border enzymes are digested ____
intraluminally; at surface
summarize nutrient breakdown
- lumen enzymes
- brush border enzymes
- nutrient transporters
- intracellular!!!
what are the 4 reasons the pancreas does not digest itself
- enzymes are synthesized as inactive zymogens
- zymogens are packaged in granules
- in granules there is a trypsin inhibitor
- activating enyme found in GI tract
the control of pancreatic secretion is both ____ and _____ mediated
neurally, hormonally
the cephalic, gastric, and intestinal phase stimulates the
vagus nerve
what phase of digestion secretes CCK and secretin
intestinal phase
gastric motility is inhibited by what hormone
secretin
____ entering the proximal duodenum reults in the release of CCK
lipids
gallbladder contraction is mediated by
CCK
secretion of bicarbonate-rich fluid by the pancreatic duct does what
- neutralizes gastric pH
- provides optimal pH for pancreatic and brush border enzyme function
- increase solubility of bile and fatty acids
why does vomiting cause metabolic alkalosis
patient vomits acidic content so H+ ions. do not trigger bicard production
what is required for B12 absorption
intrinsic factor
summarize B12 absorption
- B12 binds to intrinsic factor
- intrinsic-B12 complexes are recognized by receptors on apical membrane of ileum epithelium
- transport to blood strea
T/F: Intrinsic factor in the dog is made in the stomach and pancreas
TRUE
what are the 3 causes of B12 deficiency
- exocrine pancreatic insufficiency (cats -failure to make intrinsic factor)
- small intestinal bacterial overgrowth (bacteria consume B12)
- malabsorptive disease of the ileum (failure to absorb B12)
