B6-064 Growth Hormone/Prolactin Flashcards

1
Q

the arcuate nucleus in the hypothalmus secretes what in the GH pathway?

A

growth hormone releasing hormone (GHRH)

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

secondary triggers for the release of GHRH [4]

A

increased amino acid levels
hypoglycemia
decreased fatty acids in blood
exercise

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

GHRH goes into the […] to stimulate somatotropes to secrete GH

A

adenohypophysis

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

GHRH goes into the adenohypophysis to stimulate […] to secrete GH

A

somatotropes

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

GHRH goes into the adenohypophysis to stimulate somatotropes to secrete […] into the blood

A

growth hormone (GH)

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

how does GH stimulates the production of IGF type 1

A
  1. some GH binds to tyrosine kinase-like receptor
  2. stimulates JAK/STAT activation
  3. STAT goes into the nucleus and stimulates the production of IGF1 (insulin growth factor 1)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

some GH stimulates […] in the liver

A

gluconeogenesis

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

how does GH trigger lipolysis

A

GH binds to hormone sensitive lipase

HSL initiates lipolysis –> more glycerol available for gluconeogenesis

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

[…] stimulates amino acid uptake

A

GH via IGF1

**activate channels for amino acids on skeletal cell membranes

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

stimulates amino acids to link together to produce myofibrils –> hypertrophy

A

IGF1

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

regulates osteoblasts and osteoclasts to encourage appositional growth and endochondral ossification of bones

A

IGF1

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

IGF1 stimulates the production of […], which is crucial to endochondral ossification

A

collagen type 1

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

stimulates chondroblasts to differentiate, increase in size, and proliferate resulting in interstitial growth

A

IGF1

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

modified apocrine glands designed to produce milk

A

mammary glands

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

simulates the production of milk by alveolar cells

A

prolactin

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

tube-like structures made up of alveolar glands

A

lobules

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

anchor the breast to the posterior wall

A

suspensory ligaments

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

little tubes that drain the lobules

A

lactiferous ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

dilation of lactiferous duct just behind the nipple

A

lactiferous sinuses

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

prolactin is synthesized by […] in the anterior pituitary

A

lactotropes

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

prolactin is synthesized by lactotropes in the […]

A

anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

prolactin inhibiting hormone (dopamine) are secreted by the

A

hypothalamus

**go through hyophyseal portal system to anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

binds to D2 receptors to inhibit lactotropes

A

prolactin inhibiting hormone
[dopamine]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

thyrotropin-releasing hormone (TRH) is secreted by the […] nucleus

A

paraventricular nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

binds to specific receptors to stimulate prolactin secretion via lactotropes

A

thyrotropin-releasing hormone (TRH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

how does breast feeding provide a direct stimulus of prolactin? [2]

A

baby suckling triggers mechanoreceptors to release oxytocin –> stimulates production of prolactin

baby sucking stimulates PVN to release more TRH –> stimulates lactotropes to produce prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

high levels of […] are extremely important to prolactin stimulation

A

estrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

estrogen stimulates the production of prolactin directly via the […] and indirectly by […]

A

direct: via the lactotropes
indirect: inhibits the arcuate nucleus from secreting PIH (dopamine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

extremely high levels of estrogen inhibit […] effect on alveolar cells

A

prolactin’s

**as estrogen levels fall after birth, prolactin starts effecting alveolar cells

30
Q

prolactin activates the JAK/STAT pathway to transcribe mRNA into [2]

A

milk proteins: casein, lactoferin

kinases that phosphorylate different channels on the cell membrane to allow ions, IgA, lipids, and vitamins into breast milk

31
Q

GH and prolactin are both secreted by the

A

anterior pituitary

32
Q

stimulates linear growth and muscle mass via IGF1 secretion by liver

A

GH

33
Q

increases insulin resistance

A

GH

34
Q

GH is released in pulses in response to

A

GHRH

35
Q

secretion of GH is increased in what conditions?

A

sleep
hypoglycemia
stress
puberty
exercise

36
Q

secretion of GH is decreased in what conditions?

A

aging
obesity
hyperglycemia
somatostatin

37
Q

excess secretion of GH (i.e. due to pituitary adenoma) causes

A

acromegaly in adults
gigantisim in children

38
Q

treatment for excess secretion of GH

A

somatostatin analog (octreotide)
surgery

39
Q

how does IGF1 affect bone? [6]

A

increases:
amino acid uptake
protein synthesis
DNA/RNA synthesis
chondroitin sulfate
collagen
cell size and number

40
Q

how does IGF1 affect skeletal muscle?

A

increases:
amino acid uptake
protein synthesis

41
Q

how does IGF1 affect adipose?

A

decreased glucose uptake
increases lipolysis

42
Q

structurally homologous to GH

A

prolactin

43
Q

stimulates milk production in breast

A

prolactin

44
Q

inhibits ovulation in females and spermatogenesis in males by inhibit GnRH synthesis

A

prolactin

45
Q

excessive amount of […] is associated with decreased libido

A

GH

46
Q

prolactin secretion from the anterior pituitary is inhibited by

A

dopamine

47
Q

TRH increases […] secretion

A

prolactin

48
Q

inhibit prolactin secretion and can be used in treatment of prolactinoma

A

dopamine agonists

49
Q

what drug classes stimulate prolactin secretion?

A

dopamine antagonists
estrogens

50
Q

excess GH in adults, typically caused by pituitary adenoma

A

acromegaly

51
Q

increased GH in children causes

A

gigantism

**due to increased linear bone growth

52
Q

stimulates IGF-1 secretion from liver

A

GH

53
Q

symptoms of acromegaly

A

enlargement of hands and feet
macroglossia
macrognathia
impaired glucose tolerance

54
Q

GH stimulates […] receptors

A

non-tyrosine kinase

JAK/STAT pathway

55
Q

IGF-1 signals through […] receptors

A

tyrosine kinase

56
Q

treatment for acromegaly and hyperprolactinemia

A

octreotide

57
Q

how does IGF-1 enter systemic circulation?

A

hepatic vein –> IVC

58
Q

GH stimulates the production of […] in the liver

A

IGF-1

59
Q

what hormones use a receptor tyrosine kinase pathway? [4]

A

insulin
IGF-1
PDGF
FGF

Get Found IN the MAP

60
Q

postpartum symptoms of
fatigue
anorexia
poor lactation
loss of pubic and axillary hair

A

Sheehan syndrome (postpartum hypopituitarism)

61
Q

prolactinoma causes […] due to compression of the optic chiasm

A

bitemporal hemianopia

62
Q

symptoms of prolactinoma in men [3]

A

decreased libido
erectile dysfunction
gynecomastia

63
Q

symptoms of prolactinoma in women [4]

A

decreased libido
galactorrhea
amenorrhea
infertility

64
Q

Sheehan syndrome is caused by

A

ischemia necrosis of the pituitary gland secondary to significant blood loss during delivery

65
Q

in Sheehan syndrome, inability to lactate is caused by

A

decreased prolactin

66
Q

in Sheehan syndrome, amenorrhea is caused by

A

decreased LH/FSH

67
Q

cause headaches and bilateral hemianopia

A

prolactinomas

68
Q

why does a prolactinoma in women cause amenorrhea and infertility?

A

inhibition of gonadotropin releasing hormone due to excessive prolactin

69
Q

used to treat prolactinoma

A

dopamine agonists

(bromocriptine, cabergoline)

70
Q

medications that can be used to stimulate prolactin secretion

A

dopamine antagonists (antipsychotics, metoclopramide)
estrogens (OCPs, pregnancy)

71
Q
A