General Flashcards
What are the 3 cardinal abnormalities in Type 2 Diabetes Mellitus?
- Insulin resistance - earliest detectable abnormality
- Defective insulin secretion
- Increase glucose production by the liver
What are the cells of the pancreas? And what hormones do they produce?
(chap 33, p1338)
Alpha - glucagon
Beta - (60%) insulin
Delta - somatostatin
Gamma - polypeptide Y
Epsilon - Ghrelin
The main stimulus for insulin secretion is _____________. (chap 33, p1338)
Glucose
Glucose enters the pancreatic beta cells via the ________________. (chap 33, p1339)
Isoform 2 of the glucose transporter (GLUT2)
ATP sensitive K channels in the pancreatic beta cells are __________ and __________. (chap 33, p1339)
Sulfonylurea receptors (SUR) and potassium inward rectifiers (Kir 6.1 and Kir 6.2)
(In the beta cell, the SUR1/Kir6.2) pairs constitute the K ATP channel)
Effect of sympathetic and parasympathetic stimulation in the release of insulin and glucagon. (chap 33, p1339)
Sympathetic: inhibits insulin, potentiates glucagon secretion
Parasympathetic: stimulates insulin, inhibits glucagon secretion
The full complement of beta cell mass is established within the __________ age. (chap 33, p1339)
5 years of age.
The average lifetime of pancreatic beta cells is about ___________ years. (chap 33, p1339)
25 years
The endocrine pancreas has a large functional reserve. The pancreatic insulin content is __________ units. (chap 33, p1339)
200-250units
Which of the following statements about insulin is false? (chap 33, p1340)
A. Each insulin granule contains electron-dense core composed of tightly packed crystals of insulin hexamers stabilized by 1 calcium and 2 zinc ions.
B. Only a small fraction (<1%) of granule insulin is secreted in response to acute in vitro stimulation
C. Granule half-life is <5 days
D. Younger granules are fewer but more mobile than older granules even if they come from deep in the cytoplasm.
E. None of the above
E. None of the above
Which of the following statements about C-peptide is false? (chap 33, p1340)
A. C-peptide is co-secreted with insulin in equimolar amounts
B. C-peptide is not extracted by the liver
C. Half of the C-peptide clearance occurs through the liver
D. Measurements of the ratio of urinary C-peptide to creatinine is well correlated with postprandial C-peptide and can be used as indicator of residual beta-cell function in patients with T1DM
C. Half of the C-peptide clearance occurs through the kidney
Which of the following statements about C-peptide is false? (chap 33, p1340)
A. C-peptide is co-secreted with insulin in equimolar amounts
B. C-peptide is not extracted by the liver
C. Half of the C-peptide clearance occurs through the liver
D. Measurements of the ratio of urinary C-peptide to creatinine is well correlated with postprandial C-peptide and can be used as indicator of residual beta-cell function in patients with T1DM
C. Half of the C-peptide clearance occurs through the kidney
The fraction of portal insulin that is removed by the liver in its first pass is about _______%.(Chapter 33, p 1341)
65%
(The overall contribution of the liver (first pass plus recirculation is approximately 80%)
What are the main modes of beta cell response? (Chapter 33, p 1342)
1) First phase or acute insulin secretion
2) Glucose sensitivity
3) Potentiation of insulin secretion
The insulin response during a hyperglycemic clamp challenge is ____________. (Chapter 33, p 1344)
Biphasic
What are the Type 1 DM associated autoantibodies? (Chap 36, p1404)
1) anti-insulin autoantibodies (IAA)
2) anti glutamic acid decarboxylase (GAD)
3) anti insulinoma associated antigen 2 (IA2A)
4) anti zinc transporter 8 (ZnT8A)
What the risk of an individual to develop Type 1 DM if his father also has Type 1 DM? (Chap 36, p1410)
4.6%
What is the risk for an individual to develop Type 1 DM if he has a dizygotic twin with Type 1 DM? (Chap 36, p1410)
6%
What is the risk for an individual to develop Type 1 DM if both of his parents have Type 1 DM? (Chap 36, p1410)
10%
If two or more anti-islet autoantibodies are present in a given individual, what is the 10-year risk for developing diabetes? (Chap 36, p1408)
60-75%
Cytotoxic T cells induce beta cell necrosis following the release of cytolytic granules containing _______________ and ____________. (Chap 36, p1406)
Granzymes and perforin
What are the 6 characteristics of islet cells in Type 1 Diabetes? (Chap 36, p1406)
Insulitis
Loss of beta cells
Hyper expression of class I MHC
Beta cell necrosis/apoptosis
Diminished insulin in remaining beta cells
Beta cell expression of interferon-a
What are the 7 characteristics of pancreas in Type 1 Diabetes? (Chap 36, p1406)
Decreased overall weight
Atrophy of dorsal region
Exocrine atrophy
Hydrophic change
Composed of pseudoatrophic islets in Type 1A
Lobular loss of beta cells
Heterogenous lobular insulitis
What is the second physiologic defense against hypoglycemia? (Williams Chap 37, p 1529)
Increase in GLUCAGON secretion by pancreatic islet alpha cells.
What is the second physiologic defense against hypoglycemia? (Williams Chap 37, p 1529)
Increase in GLUCAGON secretion by pancreatic islet alpha cells.
Most common cause of hypoglycemia? (Williams Chap 38, p 1531)
Drugs
What are the 3 forms of HAAF?
(Williams Chap 38, p 1536)
- Antecedent hypoglycemia-related HAAF
- Exercise-related HAAF
- Sleep-related HAAF
What are the 3 forms of HAAF?
(Williams Chap 38, p 1536)
- Antecedent hypoglycemia-related HAAF
- Exercise-related HAAF
- Sleep-related HAAF
What are the risk factors for Hypoglycemia-Associated Autonomic Failure (HAAF)?
(Williams Chap 38, p 1537)
- Absolute endogenous insulin deficiency
- Prior history of severe hypoglycemia or impaired awareness of hypoglycemia, or both, and recent antecedent hypoglycemia, prior exercise, or sleep
- Aggressive glycemic therapy
