L13/14

Question 1

True or False: For a person of normal weight, insulin secretion is normal. However, as they become obese and develop T2DM, there will have a moderate increase of insulin secretion until, finally, they will be obese and have BELOW NORMAL insulin secretion

Answer 1

True

Question 2

True or False: In T1DM, there is decrease in glucose uptake by cells and increase in glycogenolysis and gluconeogenesis

Answer 2

True

Question 3

True or False: In DM, there is decrease in effective insulin and increase in glucagon. As a result, ketone synthesis in liver + glycogenolysis/gluconeogenesis will increase (leading to elevated glucose)

Answer 3

True

Question 4

Ineffectiveness of intraislet insulin to inhibit glucagon secretion from alpha cells is characteristic of:
A. Early T2DM
B. Late T2DM

Answer 4

A. Early T2DM

Question 5

Severe hyperglycemia and HHS is characteristic of:
A. Early T2DM
B. Late T2DM

Answer 5

B. Late T2DM

Question 6

Which type of DM is associated with:
- Decreased insulin-stimulate glucose intake
- Increased hepatic gluconeogenesis

Answer 6

T2DM

Question 7

Diabetic ketoacidosis is a serious complication of which DM?

Answer 7

T1DM

Question 8

If pancreatic beta-cells are functioning properly, insulin resistance always results in ____ but does not always result in ____

Answer 8

hyperinsulinemia; hyperglycemia

Question 9

True or False: Hyperglycemia is most patients diagnosed with T2DM is the result of both insulin resistance and pancreatic beta cell dysfunction

Answer 9

True

Question 10

True or False: If pancreatic beta cell function is impaired, plasma glucose CAN be normal, as long as target tissues efficiently utilized glucose

Answer 10

True

Question 11

True or False: In impaired insulin secretion, there may be decrease responsiveness (decrease beta cell mass) and increased sensitivity (of beta cells to plasma glucose)

Answer 11

False -
There will be DECREASED responsiveness and sensitivity!

Question 12

Glucose sensitivity, synthesis of pre-pro-insulin, processing of pro-insulin, and reduced beta cell mass are characteristic of:
are characteristic of impaired ___ secretion

Answer 12

insulin

Question 13

If target cells are insulin resistant, it means that insulin cannot inhibit what two processes?

Answer 13

1) Hepatic gluconeogenesis
2) Glucagon secretion

Question 14

Result of excessive adipokine secretion on insulin receptor signaling?

Answer 14

Decrease adipokine TNF-a, which decrease RTK activity

Question 15

Three effects of excessive FA oxidation?

Answer 15

1) Serine kinase activated
2) IRS-1 phosphorylated by serine
3) Tyrosine kinase unable to phosphorylate IRS-1

Question 16

True or False: Excessive FA oxidation by cells results in:
- Serine kinase activation
- Phosphorylation of IRS-1 by serine
- Accumulation of DAG

Answer 16

True

Question 17

What two molecules are elevated in obese individuals? Decreased?

Answer 17

Increased = leptin (food intake) and adipokine (insulin/glucose sensitivity)
Decrease = adiponectin (beta cell prol)

Question 18

True or False: Cortisol and GH will only work if hypoglycemia is severe and persists for hours

Answer 18

True

Question 19

What are the four counter-regulatory hormones?

Answer 19

1) Glucagon
2) Epi
3) Cortisol
4) GH

Question 20

What is the function of counter-regulatory hormones?

Answer 20

Prevent hypoglycemia

Question 21

With short-term fasting, ___ stores are used first

Answer 21

glycogen

Question 22

True or False: With continued fasting, gluconeogenesis and lipolysis increase and low plasma insulin facilitates protein/TG breakdown

Answer 22

True

Question 23

In what state are ketones made in liver?

A. Absorptive State
B. Fasting State

Answer 23

B. Fasting State

Question 24

Insulin stimulates __ in adipose tissue capillaries

Insulin enhances glucose uptake by and TG synthesis in ___

Answer 24

LPL; adipocytes

Question 25

Hydrolysis of glycogen, fat, and proteins (plus: gluconeogenesis and ketogenesis) are associated with: A. low insulin to glucagon ratio B. high insulin to glucagon ratio

Answer 25

A. low insulin to glucagon ratio

Question 26

Negative feedback loops regulate plasma glucose not plasma ___ or ____

Answer 26

insulin; glucagon

Question 27

What inhibits glucagon secretion?

Answer 27

Elevated plasma glucose, low plasma amino acids

Question 28

True or False: Plasma amino acids have the same effect on secretion of both insulin and glucagon

Answer 28

True

Question 29

True or False: Ach leads to secretion of glucagon

Answer 29

False - NE/Epi (SNS) + elevated plasma cortisol lead to glucagon secretion

Question 30

What is the threshold for glucagon secretion?

Answer 30

65-70

Question 31

As plasma glucose decreases, plasma glucagon ____

Answer 31

increases

Question 32

Absorptive phase is dominated by ___ while fasting phase is dominated by ___

Answer 32

insulin; glucagon

Question 33

What molecule is not removed via first pass metabolism and, therefore, is a good indicator of pancreatic function and initial insulin secretion?

Answer 33

C-peptide

Question 34

True or False: Parasympathetic stimulation inhibits insulin secretion

Answer 34

False - NE/EPI INHIBITS insulin secretion

Question 35

What molecule increases insulin secretion during absorptive phase?

Answer 35

GLP-1

Question 36

What are three drugs that treat T2DM and targets GLP-1/DPP-IV?

Answer 36

1) DPP-IV resistant GLP-1 analog 2) Albumin based GLP-1 3) Antagonists of DPP-IV (slow breakdown og GLP-1)

Question 37

GLP-1 can be converted to ___, which is biologically inactive

Answer 37

GLP-1 fragment

Question 38

Three stimuli that activates insulin secretions?

Answer 38

1) GLP-1/GIP 2) Increase glucose, AA/FA 3) Ach/parasympathetic stimulation

Question 39

Plasma glucose of ____ mg/dl is threshold for insulin secretion

Answer 39

80

Question 40

What is the most important stimulus for insulin secretion?

Answer 40

Plasma glucose

Question 41

Insulin secretion by beta cells involves: A. Insulin dependent glucose transporter B. Insulin independent glucose transporter (GLUT4)

Answer 41

B. Insulin independent glucose transporter (GLUT4)

Question 42

True or False: Insulin contains C-peptide + a/b chain + insulin

Answer 42

True

Question 43

Where in the beta cell does insulin synthesis occur?

Answer 43

Vesicle

Question 44

While fasting, plasma glucose should remain stable and ~ ______

Answer 44

70 to 100 mg/dl

Question 45

After a meal, plasma glucose should not be greater than ___

Answer 45

180 mg/dl

Question 46

True or False: In glucose-dependent tissues, glucose transport is regulated by insulin

Answer 46

False - in GLUCOSE-INDEPENDENT tissues, glucose transport is regulated by insulin

Question 47

Are glucose transporters always in the membrane w/r/t glucose dependent tissues?

Answer 47

Yes

Question 48

True or False: Glucose-independent tissues utilize RTK's

Answer 48

True

Question 49

Skeletal muscle, adipose tissues, and liver are examples of: A. Glucose independent tissues B. Glucose dependent tissues

Answer 49

A. Glucose independent tissues

Question 50

True or False: Skeletal muscle, adipose tissues, and liver can use glucose or fatty acids to make ATP

Answer 50

True

Question 51

What type of glucose transport is used by glucose dependent tissues? A. Insulin independent glucose transport B. Insulin dependent glucose transport

Answer 51

A. Insulin independent glucose transport

Question 52

What type of tissues have glucose transporters always present in the plasma membrane and require a concentration gradient for glucose entry? A. Glucose Dependent Tissues B. Glucose Independent Tissues

Answer 52

A. Glucose Dependent Tissues

Question 53

Brain, neurons, RBC's, renal medulla, and intestinal mucosa are examples of what type of tissues?

Answer 53

Glucose-Dependent Tissues