Lecture Final Flashcards
What does the pancreas consist of?
The right lobe which is adjacent to the descending duodenum, the left lobe which is caudodorsal to the stomach, and the body which is located at the cranial duodenal flexure, close to the pylorus
Where do the excretory ducts of the pancreas exit?
They exit the pancreatic parenchyma to enter the duodenum
Where does the pancreatic duct enter the small intestine?
At the duodenum with the bile duct at the major duodenal papilla, which opens into the duodenum itself
Where does the accessory pancreatic duct enter the duodenum?
At the minor duodenal papilla
How does the pancreas receive blood?
From the branches of both the coeliac artery and superior mesenteric artery
What artery supplies the neck, body, and tail of the pancreas with blood?
The splenic artery, which runs along the top margin of the pancreas
What is the largest pancreatic arterial branch called?
The greater pancreatic artery
Where do lymphatics in the pancreatic duct drain into?
The duodenal, hepatic, splenic and mesenteric lymph nodes
What system supplies nervous function to the pancreas?
Both the sympathetic and the parasympathetic nervous system
What is the pancreas?
A highly lobulated gland invested by a thin, loose collagenous capsule which extends as a delicate septa between lobules
What does the exocrine portion of the pancreas consist of?
Closely packed Acini tissue, which drains into a highly branched duct system
What does the endocrine portion of the pancreas consist of?
It forms the islets of Langerhaans of various sizes scattered throughout the exocrine tissue
What is the majority of pancreatic tissue composed of?
98% is dedicated to exocrine (acini), about 2% is dedicated to endocrine secretion (islets)
What are the four cell types created in the islets of Langerhaans?
Alpha (glucagon), beta (insulin), delta (somatostatin), PP cells (pancreatic polypeptide)
What is the Fed state within the pancreas?
Insulin dominates with an increase in glucose oxidation, glycogen, fat, and protein synthesis
What is the Fasted state within the pancreas?
Glucagon dominates with an increase in glycogenolysis, gluconeogenesis, and ketogenesis
What is exoystosis?
A process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane within the cell membrane
What else can glucose be used for when it is stored?
Metabolism
How is glucose driven from the blood into the cells?
A concentration gradient
What part of the pancreas secretes digestive enzymes?
The acini tissue
What does pancreatic secretion contain?
Enzymes for digesting all 3 major types of food (proteins, carbs, and fat), and large quantities of bicarbonate ions
Why are bicarbonate ions in pancreatic secretions important?
They play a role in neutralizing the acid chyme emptied by the stomach into the duodenum
What are the most important of the proteolytic enzymes?
Trypsin (most important), chymotrypsin, and carboxypolypeptidase
Which pancreatic enzyme helps digest carbs?
Amylase
What is the main enzyme for digesting fat?
Lipase, but also cholesterol esterase and phospholipase
What 3 secretions trigger pancreatic secretions?
Acetylcholine, cholecystokinin, and secretin
What is acetylcholine?
It is released from the parasympathetic vagus nerve endings as well as other cholinergic nerves in the enteric system
What is cholecystokinin?
CCK is secreted by the duodenal and upper jejunal mucosa when food enters the small intestine; it causes contraction of the gallbladder to trigger bile acids release
What is secretin?
It is secreted by the same duodenal and jejunal mucosa as CCK when highly acidic food enters the small intestine
How many phases of pancreatic secretion are there?
1 - Cephalic
2 - Gastric
3 - Intestinal
What occurs during the cephalic phase of pancreatic secretion?
About 20% of total secretion of pancreatic enzymes occurs because the brain is triggered by the thought of eating
What occurs during the gastric phase of pancreatic secretion?
About 5-10% of the total secretion of pancreatic enzymes which is triggered by the stomach once food is actually ingested
What occurs during the intestinal phase of pancreatic secretion?
About 70% of total secretion of pancreatic enzymes from the small intestine because digestion begins and enzymes are secreted
What is pancreatitis?
Acute or chronic inflammatory condition which results in intrapancreatic activation of enzymes that triggers autodigestion of the pancreas itself
What makes the pancreas digest itself with pancreatitis?
The pancreas is made of protein and trypsin that is activated from inflammation digests protein
What dogs typically become afflicted with acute pancreatitis?
Dogs greater than 5 years old, overweight and typically mini schnauzers, yorkies, and mini poodles
What cats typically become afflicted with chronic pancreatitis?
From 4 weeks to 18 years old, DSH and DLH, and also siamese cats
What is involved in the pathogenesis of pancreatitis?
Acinar cell membranes are damaged, which triggers the activation of trypsinogen, which then activates other digestive enzymes and a progressive cascade of autodigestion follows
Which animal is more likely to have smoldering, low grade chronic pancreatitis?
Cats, as their clinical signs are vague and nonspecific
How is pancreatitis typically diagnosed?
If the pet has had a recent fatty meal, falls into the identifiable risk group, and various lab results
What are some typical lab results from a pet with pancreatitis?
- CBC: neutrophilila, hemoconcentration
- Chem: azotemia, elevated ALT, ALKP and TBil
What is the test of choice for diagnosing pancreatitis?
cPLI which is a pancreatic lipase immunoreactivity test
What are the serum pancreatic enzymes which may indicate pancreatitis?
Amylase and lipase
What pancreatitis test checks for trypsin-like immunoreactivity?
TLI, it is also the test of choice for EPI is both dogs and cats