Insulin, Glucagon & Diabetes Mellitus Flashcards
Insulin ______ breakdown of lipids
inhibits
What can lipidemia cause?
- Coma
- CNS depression
- Ketone breath
- Hyperpnea
- Cardiac irregularities
T/F Proinsulin is composed of A,B, + C chains
True
T/F Growth hormones and ghrelin suppress insulin release
False; Somatostatin + Leptin
T/F Proinsulin gets cleaved into insulin & A/B peptide
False; insulin & C peptide
What kind of drugs stimulate insulin release?
Sulfonylurea
T/F High carb diet causes the release of both insulin and glucagon
False; protein
T/F Obesity stimulates insulin release
True
T/F Increased blood glucose levels suppresses insulin release
False; decreased
T/F Glucagon, GH, cortisol will suppress insulin release
False; stimulate
T/F Glucagon stimulates release of glucose to the blood
True
T/F Glucose enters the beta cells via GLUT2 transporters
True
Glucagon _______ glycogen production
decreases
T/F Glucagon promotes gluconeogenesis
True
T/F Lipidemia can cause one to have CNS depression and coma
True
What is polyuria?
Diluted urine
Insulin ______ free fatty acid uptake
increases
Fasting ______ insulin release
suppresses
How does polyuria affect NaCl levels in kidney?
Decreases
What is polydipsia?
Increased thirst
GI hormones (Incretins) _______ insulin release
Stimulate
T/F Glucagon inhibits glycogenolysis
False; stimulates
What GI hormone stimulates insulin release?
Incretins
What happens when the tyrosine kinase receptor is activated?
Causes phosphorylation of many intracellular enzymes can
Activates other enzyme which changes gene expression
What is the plasma half life of insulin?
6 minutes
When glucagon receptor is activated, what happens?
- Activates adenylyl cyclase
- Increases cAMP
- Activates protein kinase A
T1DM vs T2DM; which have a lack of insulin secretion?
T1DM
T/F The pancreas has both exocrine and endocrine cells
True
T/F Sleeping causes glucagon secretion
False; excercise
Insulin _______ glycogen production
increases
How is insulin first synthesized as?
Preproinsulin
Hyperglycemia _______ glucagon stimulation
inhibits
What enzyme catalyzes glucose to G6P?
Glucokinase
How does polyuria affect renin levels in kidney?
Increases
What enzyme degrades insulin?
Insulinase in the liver
T/F Depolarization of ATP-sensitive K channels activate voltage-gated Na+ channels to release insulin from insulin-containing vesicles
False; Ca++
What does glucagon do to the liver/adipose tissue?
Lipolysis
Insulin _______ glucose production
decreases
T/F Increased blood glucose, Increased blood free fatty acid, and increased blood amino acids stimulates insulin release
True
How many AA are found in insulin?
51 AA long
How does diabetes affect the eye?
Causes angiogenesis, which allows the new blood vessels to be leaky, which are toxic to neurons
Insulin receptor is a receptor _______ _______ + a homodimer, which each monomer has one ___ and ___ subunit
Tyrosin kinase
alpha and beta
Type 1 Diabetes Mellitus affects ____% of diabetes pt
5-10%
T1DM vs T2DM; which is likely caused by a viral infection?
T1DM
How does polyuria affect how nutrients get into the kidney?
Less nutrients because of less blood, which causes kidney failure
Binding insulin to a receptor, it causes _______ of many intracellular enzymes
phosphorylation
The two main hormones (GI hormones) are..?
GLP-1 (Glucagon-Like Peptide-1) + GIP (Gastric Inhibitory Peptides)
How does polyuria affect blood flow in kidney?
Vasoconstriction which causes less blood flow
What is polyphagia?
Extreme hunger
Glucagon _______ glucose production
increases
T1DM vs T2DM; which one affects 90-95% of pts?
T2DM
Parasympathetic stimulation _______ insulin release
stimulates
What kind of receptor is a glucagon receptor?
G-protein coupled
T1DM vs T2DM; which has a reduced sensitivity of target tissues to insulin?
T2DM
T/F High blood amino acids levels causes glucagon secretion
True
Excercise causes glucagon _____
secretion
T1DM vs T2DM; which has an onset at a later age?
T2DM
What does preproinsulin get cleaved into?
proinsulin
What is the other name for exocrine cells in the pancreas?
Pancreatic acinar cells
T1DM vs T2DM; which is the autoimmune disease?
T1DM
What kinds of chains are found in insulin?
A + B chains
Beta cells in the pancreas produce:
insulin
What can glucose form as a toxic effect?
AGE (Advanced Glycation End Products ) + polyols via aldose reductase
There are clusters of cells in the pancreas called the __________ that produces glucagon and insulin
Pancreatic Islet of Langerhans
_______ are GI hormones that increase insulin release
Incretins
T/F Sympathetic stimulation stimulates insulin release
False; Parasympathetic
Sulfonylurea drugs _______ insulin release
stimulate
T/F Parasympathetic stimulation inhibits insulin release
False; stimulates
What toxic effect can glucose bring to proteins?
Change their function (EX: protein catabolism)
Hypoglycemia ________ glucagon secretion
stimulates
T/F Hyperglycemia causes glucagon secretion
False; Hypoglycemia
Alpha cells in the pancreas produce:
glucagon
T1DM vs T2DM; which has an onset at any age, but usually around 14y.o. in the US?
T1DM
Where does proinsulin get cleaved at?
Golgi
Insulin ________ lipogenesis
stiumulates
T/F Preproinsulin is cleaved at the membrane to form proinsulin
False; cleaved at ER
What is the immediate effect of lipidemia?
Increased levels of free FA in blood
What damage can hyperglycemia bring?
- Polydipsia (increased thirst)
- Polyuria (diluted urine)
- Peripheral circulation failure
- Polyphagia (extreme hunger)
When do you see lipidemia in T1DM?
Severe case
T/F Insulin causes glycogen synthesis and glucose production in the liver
False; Glycogen synthesis + INHIBITS glucose production
T/F Staying in the fasting state suppresses insulin release
True
T/F Insulin causes synthesis of FA and inhibits breakdown of lipids
True
Insulin allows increase uptake of glucose by muscle, adipose, and many tissues except where?
Neurons
Insulin ______ synthesis of proteins
increases
