Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

COM - Endocrine > Endocrine Pancreas - 2/5 Lopez > Flashcards

Endocrine Pancreas - 2/5 Lopez Flashcards

1
Q

What are the major functions of the endocrine pancreas?

A

Regulate glucose, fatty acid, and a.a. Metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do beta cells secrete?

How much of the islet?

Located where?

A

Insulin and C peptide

60-65%

Central core

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do alpha cells secrete?

What %

Located where?

A

Glucagon

20%

Periphery of islet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do delta cells secrete?

What %

Located where?

A

Somatostatin

5%

Interspersed between alpha and beta cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does blood flow in the islet cells?

A

Blood flows 1st to capillaries in the center of the isle to pick up insulin, then flows to periphery, where it acts on alpha cells to inhibit glucagon secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does somatostatin release inhibit?

A

Glucagon and insulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What links beta cells together and alpha cells together for communication within the endocrine pancreas?

A

Gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the structure of insulin

A

Made up of alpha and beta chain, linked by 2 disulfide bridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Preproinsulin contains what 4 peptides?

A

Signal peptide, alpha and beta chains, C peptide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens to proinsulin to become active?

When is proinsulin cleaved?

A

DB for in the ER and packed into secretory vesicles in the Golgi

During packaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What kind of drugs(and names) are used to treat DM type II?

How do they work?

A

Sulfonylurea drugs - tolbutamide and glyburide

Close ATP dependent K+ channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is insulin secreted?

A

Biphasic: initially burst of preformed insulin followed by sustained secretion of newly synthesized insulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does CCK and ACh affect insulin?

Via what mechanism?

A

Stimulates insulin release

Gq -> INC intracellular [Ca]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does somatostatin affect insulin release?

Via what mechanism?

A

Inhibits it

Gi blocks cAMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does glucagon affect insulin release?

Via what mechanism?

A

Stimulates it

GLP-1 receptor -> Gq -> IP3/DAG -> [Ca] -> insulin release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the insulin receptor made of?

Which parts are located where?

What has intrinsic Tyr Kinase activity?

A

Tetramer of 2 alpha and 2 beta subunits

alpha extracellular, beta span the CM

Beta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What can insulin do to its receptor?

# of insulin receptors in starvation?
Obesity?
A

Down-regulate them

INC
DEC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the metabolic effects of insulin?

A 
GLUT4 and GLUT12 translocation to CM
Activation of phosphatases
Activation of mTORC1
Activation of SREBP1c
Inhibition of FOXO1 activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Peripheral uptake of glucose occurs via what mechanism?

What transporter?

What tissues use this method?

A

FD from peripheral cells

GLUT4

Adipose tissue, resting skeletal m.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does glucose enter skeletal muscle cells?

A

GLUT4 transporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What enzyme in the muscle converts glucose to G1P?

How does glycogen synthesis occur afterwards? (Name substrate, product enzyme)

A

Hexokinase

G1P -> glycogen via glycogen synthase

22
Q

How does insulin affect the following in muscle cells?

Glycolysis
Gluconeogensis
Protein synthesis
Protein breakdown

A

INC
DEC
INC
DEC

23
Q

F6P -> F-1,6-BP with what enzyme?

24
Q

Pyruvate -> acetyl-CoA via what enzyme?

A

Pyruvate dehydrogenase

25
What does insulin stimulate the uptake of in adipose cells?
Glucose, TAgs, F.A.'s
26
In adipose tissue what are the main actions of insulin?
Inhibit lipolysis | Stimulate fat deposition (TAGs)
27
Uptake of TGs is mediated by what enzyme?
Lipoprotein lipase (LPL)
28
What enzyme does insulin inhibit?
hormone sensitive lipase (HSL)
29
Insulin decreases what in the blood?
Glucose Fatty acids Ketoacidosis Amino acids
30
How does insulin affect the following? ``` Glucose uptake into cells Glycogen formation Glycogenolysis Gluconeogensis Protein synthesis Fat deposition Lypolysis K+ uptake into cells ```
``` INC INC DEC DEC INC INC DEC INC ```
31
How do the following affect insulin? ``` Glucagon Cortisol Exercise K+ Fasting Obesity Diazoxide GIP ACh/Vagal stimulation ```
``` stimulate Stimulate Inhibit Stimulate Inhibit Inhibit Stimulate Inhibit Stimulate Stimulate ```
32
How do sulfonylurea drugs affect insulin? Alpha-adernergic agonists?
Stimulate Inhibit
33
DM type I affects [a.a.] how? Protein breakdown? Protein synthesis? Catabolism of a.a.? Urea genesis?
DEC INC DEC INC INC
34
How does INC blood [glucose] affect the filtered load of glucose? What does this do? What is prevented? Ultimate result?
INC Exceeds reabsorption capacity of PCT Water and electrolyte reabsorption Thirst, Polyuria and excretion of Na and K
35
How does DM type I affect K, i.e. What does it cause? Why?
hyperkalemia, less K+ uptake into cells Lack of effect on Na/K ATPase
36
What does DM type I cause in patients due to ECF volume contraction? How does this happen?
Hypotension Unabsorbed glucose acts as an osmotic diuretic in the urine
37
What are 3 causes of obesity-induced insulin resistance?
Dec GLUT4 uptake of glucose Dec ability of insulin to repress hepatic glucose production Inability of insulin to repress HSL or INC LPL in adipose
38
In non-obese patients, how else can DM type II occur?
DEC insulin release by the pancreas
39
Injection of what GLP-1 analogue may treat DM type II?
Exenatide
40
What drugs treat DM type II via slow absorption of carbohydrates?
``` Alpha-glucosidase inhibitors (acarbose, miglitol) Amylin analogs (pramlintide) ```
41
What drugs are insulin sensitizers (tx for DM type II)?
Biguanide drugs ie metformin (upregulates receptors on target tissues)
42
How is glucagon synthesized? How is it stored?
Preproglucagon Dense granules until alpha cells are stimulated
43
What is the major stimulatory factor of glucagon? What else stimulates it?
DEC blood [glucose] INC a.a.
44
What accessory stimulatory factors activate glucagon?
fasting CCK ACh Beta-adrenergic agonists
45
What else will inhibit glucagon secretion?
Somatostatin INC F.A. INC ketoacid
46
What tissue does glucagon act on? What 2nd messenger does it use?
Liver, adipose cAMP
47
How does glucagon secretion affect glycogenolysis? Gluconeogenesis?
INC INC
48
What enzyme does glucagon decrease the production of? What does this do?
F-2,6,BP thus decreasing PFK Favors glucose formation
49
What effects does glucagon have in adipose tissue?
INC lipolysis Inhibits F.A. Synthesis
50
What are the intestine derived hormones? Secreted in response to what? What effect?
GLP-1, GIP GI glucose and fat Stimulate insulin secretion, inhibit glucagon, and slow gastric emptying
51
What do endocrine cells secrete?
Insulin, glucagon, somatostatin

COM - Endocrine (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions