Anterior Pituitary Hormones (prolactin + GH)

Question 1

What class of hormone is prolactin?

Answer 1

Hydrophilic peptide hormone

Question 2

What is prolactin’s target tissue?

Answer 2

Mammary Glands

Question 3

What is prolactin’s functions?

Answer 3

Lactogenesis
Growth
Ovulation inhibition

Question 4

What stimulates prolactin before or during pregnancy?

Answer 4

Estrogen and thyroid releasing hormone
(Puberty/pregnancy)
Dopamine inhibition

Question 5

What stimulates prolactin primarily after pregnancy?

Answer 5

Lactation
Sleep
Dopamine antagonist

Question 6

What inhibits prolactin?

Answer 6

Dopamine or dopamine agonists
D/C of stimuli

Question 7

What class of hormone is Growth Hormone?

Answer 7

Hydrophilic peptide hormone

Question 8

What is GH’s target tissue?

Answer 8

Liver
Adipose tissue
Muscle/other tissues

Question 9

What is the function of GH?

Answer 9

Growth and metabolism

Question 10

How does GH stimulate tissue growth?

Answer 10

GH stimulates the liver to release somatomedins which stimulates cellular proliferation

Question 11

What is the other name for somatomedin?

Answer 11

Insulin-like growth factor 1

Question 12

How and why does GH stimulate fat metabolism?

Answer 12

GH stimulates lipolysis to breakdown fat stores and free up glucose

Question 13

How and why does GH stimulate glucose metabolism?

Answer 13

GH inhibits glucose uptake and stimulates liver glucogenolysis (breakdown of glycogen) to release glucose into the bloodstream
GH does this to maintain blood glucose levels during growth

Question 14

How and why does GH stimulate protein?

Answer 14

GH stimulates uptake of protein into tissues to promote muscle building

Question 15

What stimulates GH?

Answer 15

Growth Hormone Releasing Hormone
Puberty
Hypoglycemia
Exercise
Stage 4 Deep Sleep
Dietary protein

Question 16

What inhibits GH?

Answer 16

Cortisol/glucocorticoids
Somatostatin (GHIH)
Hyperglycemia
Negative feedback loops

Question 17

What is a cortisol syndrome that can inhibit GH?

Answer 17

Cushing’s syndrome

Question 18

Why does cortisol inhibit GH?

Answer 18

Cortisol stimulates a catabolic reaction in the body which negates GH’s anabolic function

Question 19

What are some specific meds that can inhibit GH, especially in children?

Answer 19

Prednisone, dexamethasone, prednisolone

Question 20

What are three growth syndromes that can be caused by dysfunctional GH?

Answer 20

Dwarfism
Acromegaly
Gigantism

Question 21

What is dwarfism caused by?

Answer 21

Too little GH before puberty
(impaired secretion or receptors)

Question 22

What is gigantism caused by?

Answer 22

Too much GH before puberty

Question 23

What happens in gigantism?

Answer 23

Long bones and flat bones become enlarged due to too much GH before the epiphyseal plates close

Question 24

What are physical findings of gigantism?

Answer 24

Excessive height
Enlarged hands/feet/skull

Question 25

What is acromegaly caused by?

Answer 25

Excessive GH after puberty

Question 26

What are physical findings of acromegaly?

Answer 26

Height does not change (long bones are unaffected)
Flat bones are affected
Enlarged hands/feet/skull

Question 27

What is the main concern of long-term excessive GH?

Answer 27

Shortened life span

Question 28

What are other complications of long-term excessive GH?

Answer 28

Cardiomyopathy/cardiomegaly
Neuropathy of hands/feet
Diabetes
Increased risk of malignancy (3x)
Respiratory disease
Arthropathy