Pancreas

Question 1

Types of Pancreatic Receptors and what they secrete

Answer 1

1. Alpha - glucagon
2. Beta - insulin and amylin
3. Delta - somatostatin
4. Grelin

Question 2

What is special about beta cells?

Answer 2

Can regulate what other cell types do due to its central location w/in the islet

Question 3

How is insulin synthesized and structured?

Answer 3

Preproinsulin –> proinsulin –> insulin (+C peptide)

Secreted w/ C- peptide, can measure to see how much endogenous insulin they are making, greater half life than insulin

Question 4

How is ATP Released?

Answer 4

High Glucose stims Mito, produces TP to block K efflux channel –> depols membrane –> Ca enters –> Insulin is released

Question 5

Effect of Insulin on Carbohydrates?

Answer 5

Increases glucose uptake into target cells
Insulin–> phos of TK
–> GLUT4 is translocated to membrane –> allows glucose to enter
GLUT 4 not found in brain or liver

Question 6

Effect of Insulin on lipids?

Answer 6

Increase uptake of FFA into Fat
- Stims lipoprotein lipase (lipoprotein to FFA) in blood –> FFA (can cross membrane easily) to triglyceride in adipose cells

Question 7

What stimulates Insulin Secretion?

Answer 7

Glucose
AA
FFA
ACh
GIP
GLP-1

Question 8

What inhibits secretion of insulin?

Answer 8

EPI
NE
Somatostatin

Question 9

Where is glucagon made and what does it do?

Answer 9

Made in the liver

Increases glycogenolysis, increased gluconeogenesis, increased lipolysis

Question 10

Synthesis and Structure of glucagon

Answer 10

1. Major hormone to increase blood-glucose

2. Peptide hormone

Question 11

Receptor of Glucagon

Answer 11

couple to Adenylate Cyclase/PKA system

Question 12

Effect of glucagon on carbohydrate receptors

Answer 12

In liver = increased plasma glucose in the post ab state

Question 13

Effect of glucagon on proteins

Answer 13

Increased gluconeogensis (hepatic protein)

Question 14

Effect of glucagon on lipids

Answer 14

Increased Lipolysis - maintains blood glucose levels w/ high protein meals so you don’t take up too much glucose at once

Question 15

How is glucagon stimulated?

Answer 15

1. Low glucose
2. AA
3. EPI/NE
4. ACh

Question 16

How is glucagon inhibited?

Answer 16

1. Insulin
2. Somatostatin
3. FFA (energy source)
4. Amylin

Question 17

What does amylin do?

Answer 17

Peptide hormone secreted w/ insulin that inhibits glucagon secretion and slows down gastic emptying, glucose in blood will go up more slowly, supports action of insulin

Question 18

What are incretins and what do they do?

Answer 18

GIP (gluc-dependent Insulinotropoic polypeptide)

GLP-1 - preemptively secreting insulin, have glucose in your mouth and it warns the intestine food is coming

Question 19

What do EPI and NE do to glucagon?

Answer 19

stim glucagon release and glycogenolysis

Question 20

What does cortisol do to glucose?

Answer 20

Increases blood glucose

Question 21

What does growth hormone to insulin and glucose?

Answer 21

Anti-insulin effect

Elevates plasma glucose

Question 22

What is the only hormone that directly decreases plasma glucose?

Answer 22

Insulin

Question 23

Diabetes Mellitus Signs and Symp

Answer 23

1. XS thirst and frequent urination

2. TYPE 1 = weight loss

Question 24

TX for Type 1 diabetes mellitus

Answer 24

Insulin injections every day

Question 25

Etiology of T1 Diabetes

Answer 25

Autoimmune destruction of pancreatic Beta cells

50/50 gen/environment

Question 26

T2 Diabetes Etiology

Answer 26

Disorder of insulin receptor signaling
Impaired Beta cell response
Some genetic component
Obesity is an aggregative factor

Question 27

Tx of T2 Diabetes

Answer 27

Weight management, exercise, drugs to regulate Beta Cells

Question 28

What is Metabolic Syndrome (syndrome X) and what disease is it associated w/?

Answer 28

Associated w/ T2 Diabetes
Need 3 or more of the following:
1. Large Waist
2. High Serum Triglyceride Levels
3. Low HDL Cholesterol
4. High blood glucose
5. High BP

Question 29

Maturity Onset Diabetes of the Young (MODY)

Answer 29

Group of monogenic disorders causing hyperglycemia of early onset
Looks like type 2 but its a genetic disorder

Question 30

Gestational Diabetes and its TX

Answer 30

Develop diabetes during pregnancy due to hormones, goes away after birth but risk persists,
high birth weight
TX: diet and exercise

Question 31

Diabetic Complications

Answer 31

Dehydrations, frequent urination and xs thirst
Diabetic Ketoacidosis
Vascular disease (macro/micro)
Retinopathy
Neuropathy (peripheral most coommon)
Nephropathy (microvascular changes - leading cause of death)

Question 32

What is diabetic ketoacidosis

Answer 32

Can’t take up glucose into fat and muscle, so body burns fat and it will generate ketone bodies (acetone)
Blood pH goes down, can detect in breath (fruity) as acetone is breathed out

Question 33

What is the mechanism of toxicity for T2 Diabetes?

Answer 33

1. Advanced glycation end products (AGEs) - proteins bound w/ sugar
2. Oxidative Damage
3. Inflammation
4. Changes in 2nd messenger systems
5. Changes in GF signaling (VEGF)
6. Diversion of glucose into other metabolic pathways and xs glycolysis

Question 34

What do the mechanism of toxicity ultimately cause in T2 Diabetes?

Answer 34

1. Capillary basement membrane thickening
2. Inflammatory signals
3. ROS
4. Changes in Growth factor signaling - directly from low insulin

Question 35

What is insulin shock?

Answer 35

Plasma insulin too high
You get a decrease in plasma glucose and brain won’t get enough glucose
Symp: confusion, disorientation, impaired judgement (can be dangerous if along)
Result in coma/death
need some sugar