Endocrine - Hormones III (Parathyroid, Pancreas, Adrenal, and Gut)

Question 1

How does PTH affect Ca and P?

Answer 1

Increases Ca
Decreases P (by inhibiting resorption in the kidney)

Question 2

What pathway does PTH activate?

Answer 2

Adenylyl cyclase and cAMP

Question 3

What move Vit D3 from skin or intestine to bloodstream?

Answer 3

Vitamin D-binding protein

Question 4

What is the major form of vitamin D found in the blood?

Answer 4

25(OH)-D3

Question 5

Where is 25(OH)-D3 converted to 1,25(OH)2-D3? By What?

Answer 5

Renal tubule

By 1alpha-hydroxylase

Question 6

Hypocalcemia markedly increases what?

Answer 6

1 alpha-hydroxylase

Question 7

Where is calcitonin produced?

Answer 7

Parafollicular C cells of thyroid

Question 8

How do parafollicular cells know to release calcitonin?

Answer 8

By sensing high serum calcium

Question 9

When is ANP secreted? Where?

Answer 9

Secreted by right atrium when high NaCL and/or when volume of exctracellular space expands

Question 10

What do alpha, beta, and delta cells of the pancreas secrete?

Answer 10

Alpha - glucagon
Beta - insulin
Delta - somatostatin

Question 11

What does insulin do?

Answer 11

Stimulates glycogenesis and glycolysis (uptake of glucose into cells)

Question 12

How many disulfide bonds are in Insulin? Where?

Answer 12

3 –
2 connect alpha and beta chain
1 is within alpha chain

Question 13

What type of receptor does insulin bind to?

Answer 13

Tyrosine kinase receptor

Question 14

How does insulin stimulated cascade differ from cAMP or cGMP cascades?

Answer 14

No second messender

Question 15

Where is glycogen stored?

Answer 15

Liver and skeletal muscle

Question 16

What does glucagon stimulate?

Answer 16

Gluconeogenesis and glycogenolysis

Question 17

What pathway does glucagon act through?

Answer 17

cAMP

Question 18

Where is pancreastic polypeptide produced? What does it increase?

Answer 18

F-cells of pancreas

Regulates glycogenolysis

Question 19

Where is somatostatin produced? What does it inhibit?

Answer 19

Produced in delta-cells

Inhibits glucagon and insulin secretion

Question 20

What are the two major adrenal medullary hormones? What additional enzyme can convert one to the other?

Answer 20

NE
Epi
Phenylethanolamine-N-Methyltransferase (PNMT) - converse NE to Epi

Question 21

What AA is NE and Epi derived from?

Answer 21

Tyrosine

Question 22

What does NE bind to? Epi?

Answer 22

NE - a1, a2, B1

Epi - a1, a2, B1, B2

Question 23

What intracellular cascades do a1, a2, and B1 stimulate?

Answer 23

a1 - Gq (IP3)
a2 - Gi (inhibits adenylyl cyclase)
B1 - Gs (stimulates adenylyl cyclase)

Question 24

What hormone stimulates appetite?

Answer 24

Ghrelin

Question 25

What hormone stimulates acid and pepsin secretion?

Answer 25

Gastrin

Question 26

What stimulates release of bicarb and water?

Answer 26

Secretin

Question 27

What hormone increases secretion of digestive enzymes from the pancreas?

Answer 27

CCK

Question 28

What hormone relaxes the GI, inhibiting acid and pepsin secretion?

Answer 28

VIP

Question 29

What hormone/peptide suprresses glucose-induced insulin secretion?

Answer 29

Pancreatic polypeptide

Question 30

What hormone controls feeding behavior and energy homeostasis?

Answer 30

Neuropeptide tyrosine