Endocrine Pancreas Flashcards
Match each cell type of the pancreas to what it produces:
- A cells
- B cells
- D cells
- F cells
- glucagon
- insulin
- somatostatin
- pancreatic polypeptide
Term for “nests” of cells in pancreas
Islets of Langerhans
______ is for glucose mobilization/usage while ______ is for glucose storage.
glucagon
insulin
What is the function of somatostatin?
inhibits endocrine pancreas (regulatory)
ALSO has paracrine action
What is the function of pancreatic polypeptide produced by F cells?
inhibits endocrine pancreas (regulatory)
Insulin’s effects are opposed by _________ hormones.
diabetogenic
What are the 4 diabetogenic hormones which oppose insulin?
- glucagon
- cortisol
- epinephrine
- growth hormone
What 4 things (not hormones) inhibit insulin?
- somatostatin
- exercise
- stress
- fasting
List the 3 steps and structures of insulin synthesis.
Pre-proinsulin –> Proinsulin –> Insulin
What has to occur for Proinsulin to be converted to Insulin?
C-peptide is cleaved
What is clinically useful about C-peptide cleaved during insulin synthesis?
released in urine and used as marker for insulin production
Proinsulin is (active/inactive) while insulin is (active/inactive).
inactive
active
What two molecules inhibit the conversion of insulin from proinsulin?
- pancreastatin
- amylin
Amylin is only in what 3 animal types?
- cats
- primates
- dogs with insulinomas
List the steps of glucagon synthesis.
Pre-proglucagon (inactive) –> Glucagon (active)
What occurs for Pre-proglucagon to be converted to Glucagon?
signaling peptide is cleaved
Insulin must bind to a _______ to have an effect.
receptor
What is unique about insulin receptors?
have an alpha and beta subunit
When insulin binds the its receptor, there is a (phosphorylation/dephosphorylation) of _______ on (alpha/beta) subunit which allows for its activation.
phosphorylation
tyrosine kinase
beta
Match whether insulin increases or decreases the following:
- glucose transport
- blood glucose
- gluconeogenesis
- glycogen & triglyceride synthesis
- increase
- decrease
- decrease
- increase
Glucagon uses a G__ pathway to activate _________.
s (stimulatory)
glycogenolysis
List the order of Gs pathway glucagon uses to activate glycogenolysis.
Glucagon –> adenylate cyclase –> ATP –> cAMP –> PKA activated = glycogenolysis
What 3 actions does glucagon have on the liver?
- up gluconeogenesis
- up glycogenolysis
- down glycogen synthesis
What does glucagon do to protein catabolism and lipolysis?
increases them
In an insulin deficiency, what 2 things occur in the liver?
increased glycogenolysis + gluconeogenesis
Insulin deficiency leads to hyperglycemia which leads to ________.
osmotic diuresis
Osmotic diuresis as a result of insulin deficiency leads to what 3 things?
- dehydration
- hypovolemia
- hypotension
_______ inhibits insulin and glucagon to balance their levels in the body.
somatostatin
What two things stimulate somatostatin?
amino acids
glucose
