Endocrine I

Question 1

what are the hormones secreted from the endocrine pancreas and their cells of origin? and % breakdown of cells in islet of langerhans

Answer 1

glucagon- alpha cells- 20%
insulin- beta cells- 70%
somatostatin- delta cells- 10%

Question 2

what does somatostatin do?

Answer 2

inhibits insulin, glucagon and GH

Question 3

how does insulin antagonize glucagons effect?

Answer 3

driving glucose uptake and thus decreasing blood sugar

Question 4

how does glucagon antagonize insulins effect?

Answer 4

stimulating hepatic glucose release and increasing blood sugar

Question 5

what is a normal blood sugar

Answer 5

4-6mM = 80-100mg/dL

Question 6

what is the main regulator of pancreatic hormones?

Answer 6

glucose

Question 7

what things stimulate insulin?

Answer 7

glucose (hyper)
amino acids
incretins (GIP, GLP)
glucagon
sulfonylurea drugs

Question 8

what things inhibit insulin

Answer 8

somatostatin
NE/Epi and cortisol
fasting/exercise

Question 9

what things stimulate glucagon?

Answer 9

glucose (hypo)
amino acids
NE/Epi and cortisol
exercise and fasting

Question 10

what things inhibit glucagon?

Answer 10

incretins (GIP, GLP)
insulin
somatostatin

Question 11

explain the mechanism of action of glucose binding to beta cells?

Answer 11

glucose binds GLUT 2 R on pancreatic beta cell
closes the K channel
depolarizes beta cell
opens Ca channel
insulin is released

Question 12

what do incretins (GIP and GLP) stimulate?

Answer 12

they are either broken down quickly by DPP4

OR they go to the pancreas to stimulate insulin secretion and lower glucagon.

Question 13

what can make incretins work better?

Answer 13

DPP4 antagonist

Question 14

is insulin anabolic or catabolic? and what does it cause in skeletal muscle, liver, and adipose tissue

Answer 14

anabolic
AA uptake in skeletal muscle
suppress hepatic glucose production
adipose inhibit lipolysis

Question 15

is glucagon anabolic or catabolic? and what does it cause in skeletal muscle, liver, and adipose tissue

Answer 15

catabolic
no effect skeletal muscle
hepatic glycogen breakdown, sugar formation, ketone formation
adipose lipolysis

Question 16

what tissue is responsible for type 2 diabetes?

Answer 16

skeletal muscle, primary glucose storage

Question 17

what controls glut4?

Answer 17

Atk pathway stimulates GLUT4 vasible to translocate

Question 18

what is type 1 diabetes?

Answer 18

loss of beta cells due to autoimmune distruction

triggered by environmental factor

Question 19

how do we develop type 2 diabetes?

Answer 19

insulin resistance (inactivity and genetics)
obesity
beta cell hyperplasia (normal glucose/high insulin)
beta cell fatigue (high glucose/ high insulin)
beta cell failure (high glucose/ low insulin

Question 20

how do we know that insulin resistance (inactivity and genetics) precede obesity for type 2 diabetes?

Answer 20

research shows that from just two weeks of inactivity insulin and glucose levels increased

Question 21

what causes someone to develop insulin resistance?

Answer 21

JNK binds and phosphorylates the syr molecule in the Atk pathway and GLUT4 vesicles are not translocated
due to oxidative stress

Question 22

what does insulin resistance mean about how much insulin must be released to create the same response as before?

Answer 22

more insulin must be released because the curve is shifted to the right

Question 23

OGTT

Answer 23

oral glucose tolerance test

Question 24

HbA1C

Answer 24

hemoglobin that is covalently bound to hemoglobin and a test for diabetes

Question 25

what does elevated HbA1C increased the risk of

Answer 25

``` mortality CVD/Stroke CKD Cancer retinopathy/neuropathy ```

Question 26

what is a normal HbA1C?

Answer 26

6% >7.6% is poor blood glucose 114

Question 27

what does HbA1C predict preop in non diabetic pts?

Answer 27

mortality | acute kidney injury

Question 28

what is the leading cause of CKD and ESRD?

Answer 28

diabetes

Question 29

DKA

Answer 29

diabetic ketoacidosis ketones (blood acids elevated) sugar elevated dehydration and coma

Question 30

what are the symptoms of someone with insulin resistance?

Answer 30

``` low HDL high triglycerides obesity hypertension NAFLD ```

Question 31

why is GH release pulsatile?

Answer 31

circadian rhythm but also tied to nutrition, metabolism and hormones

Question 32

why is GH surge at night significant?

Answer 32

growth and repair during rest

Question 33

why effect would high carb meal before bed have?

Answer 33

reduced GH pulses, affect growth and repair in adults

Question 34

children what are the thyroid hormones, GH and androgens doing?

Answer 34

high T4, limited GH pulses, limited androgen

Question 35

puberty what are the thyroid hormones, GH and androgens doing?

Answer 35

normal T4, androgens increase GH pulses and increases IGF1

Question 36

aging what are the thyroid hormones, GH and androgens doing?

Answer 36

reduced T4, GH, and androgen effectiveness

Question 37

what does the peak in rate of growth for puberty correspond with?

Answer 37

peak in concentration of IGF-1 in serum

Question 38

what are the three problems that start before puberty? GH

Answer 38

gigantism: GH overexpression pituitary dwarfism: GH deficiency achondroplasia (w/o cartlidge): not related to GH

Question 39

what are the two problems that start after puberty? GH

Answer 39

acromegaly: GH overexpresion, bone growth in face | larons syndrome: GHR insensitivity (no IGF1)

Question 40

what is special about larons syndrome?

Answer 40

they are resistant to cancer and type 2 diabetes

Question 41

the pt has a lesion in the ant pit, elevated IGF1, elevated GH and no GHRH, what does the pt have?

Answer 41

acromegaly

Question 42

why is GH diabetogenic?

Answer 42

it increases insulin resistance

Question 43

when should normal insulin peak and return to baseline?

Answer 43

peak at 30 min | baseline after 3 hr