Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medical Physiology > Hypothalamic Adenohypophyseal Axis > Flashcards

Hypothalamic Adenohypophyseal Axis Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

What produces GH

A

Somatotrophs

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

2nd msgr gonadotroph

A

PLC

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

2nd msgr thyrotroph

A

PLC

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

Corticotroph 2nd messenger

A

AC

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

somatotroph 2nd messenger

A

AC

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

lactotroph 2nd messenger

A

decrease AC, increase K, decrease Ca

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

what are the catecholamines

A

dopamine, epi, norepi

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

what hormones are cleaved from POMC mRNA?

A

ACTH and MSH; also beta endorphin and beta lipotropin

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

what is secreted from the arcuate nucleus

A

MSH, dopamine, GHRH, somatostatin

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

what is secreted from supraoptic nucleus

A

oxytocin, ADH (mostly)

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

what is secreted from preoptic nucleus

A

GnRH

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

what is secreted from periventricular nucleus

A

somatostatin

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

what is secreted from paraventricular nucleus

A

oxytocin (mostly), ADH, TRH, CRH

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

what do beta endorphins do

A 
systemically reduce stress and maintain homeostasis
locally amygdala (memory, emotion, pain perception) and hypothalamus (homeostasis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is substance P

A

neurotransmitter involved in pain responses

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

what are endorphins

A

released by the pituitary gland in order to block pain perception

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

what do endorphins bind to

A

bind to opiate receptors located on the presynaptic membrane and block the release of substance P

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

what causes release of melanin

A

melanocytes are stimulated by MSH (facilitated by UV light)

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

what is released by the anterior pituitary

A

ACTH/MSH, TSH, LH, FSH, prolactin

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

what cells release TSH

A

thyrotrophs

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

what cells release FSH and LH

A

gonadotrophs

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

what cells release GH

A

somatotrophs

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

what cells release prolactin

A

lactotrophs

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

what cells release POMC hormones

A

corticotrophs

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

cell type majority in anterior pituitary

A

somatotrophs – GH

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

metabolism of growth hormone

A

liver

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

metabolism of prolactin

A

kidney

28
Q

primary function of GH

A

systemic increase in body weight, size, length, protein synthesis, mitosis

29
Q

half life of GH

A

10min is 1-5ng/ml unbound

30
Q

half life of prolactin

A

15-20min, 10ng/ml unbound

31
Q

primary function of prolactin

A

milk synthesis, breast development, osmoregulation, poss carb metabolism

32
Q

when is GH released

A

primarily at night, rhythmically

33
Q

what stimulates GH?

A

GHRH

  1. hypoglycemia
  2. decrease in FFA
  3. increase in arginine
  4. fasting or decreased calories
  5. ghrelin
  6. REM sleep
  7. stress/exercise
  8. puberty
  9. sex hormones (testosterone)
34
Q

what inhibits GH

A

GHIH

  1. hyperglycemia
  2. increase in FFA
  3. increase in GH
  4. increase in somatostatin that is from the anterior pituitary
35
Q

how does GHRH stimulate GH release

A

binds to Gs, stimulates AC, increase cAMP, stimulate PKA, P proteins stimulate GH mRNA, GH released

36
Q

how does GHIH inhibit GH release

A

GHIH binds to Gi which inhibits AC

37
Q

what regulates growth hormone secretion?

A
  1. negative feedback from GHRH to hypothalamus
  2. negative feedback from somatomedins (insulin like GF) to anterior pituitary
  3. positive signal from somatomedins to hypothalamus to release somatostatin
  4. positive signal from GH to hypothalamus to release somatostatin
38
Q

what hormone is secreted by the liver?

A

insulin like growth factor (IGF) is stimulated by GH and released by the liver

39
Q

describe the IGF receptor

A

85% similar to insulin receptor, is a tyrosine kinase domain

40
Q

what is the growth hormone signal transduction pathway

A

tyrosine kinase JAK STAT MAPK pathway

41
Q

action of GH on liver

A

liver to produce somatomedins (IGF) to

  1. cartilage and bone (growth)
  2. muscle and other organs (protein synthesis and growth)
42
Q

action of GH on adipose

A

lipolysis and release of FFA

43
Q

does GH directly act on bone and muscle/organs?

A

indirectly through liver

44
Q

action of GH on most other tissues

A

decreased glucose utilization

45
Q

what occurs with hyposecretion of GH

A

before puberty: pituitary dwarfism

unrelated to GH: non pituitary dwarfism

46
Q

what occurs with hypersecretion of GH

A

before puberty: gigantism

after: acromegaly

47
Q

what occurs in achondroplasia?

A

fibroblast growth factor receptor problem – cannot contribute to production of collagen, short bone and cartilage

48
Q

what occurs in laron dwarfism

A

GH receptor mutation

49
Q

what is the blood response to insulin

A

decreased blood glucose, FFA, AA

50
Q

blood response to glucagon

A

increased blood glucose and FFA, decreased AA (kinda)

51
Q

blood response to GH

A
  1. increased blood glucose (decreased organ utilization)
  2. increased FFA (increased lipolysis and increased release of FFA from adipose)
  3. decreased AA (increased protein synthesis and growth)
52
Q

which hormones use AC and cAMP?

A
  1. ACTH
  2. LH
  3. FSH
  4. TSH
  5. ADH (v2)
  6. hCG
  7. MSH
  8. CRH
  9. calcitonin
  10. PTH
  11. glucagon
  12. beta 1 and 2 receptors
  13. GHRH (both cAMP and IP3/DAG)
53
Q

which hormones use IP3/PLC

A
  1. GnRH
  2. TRH
  3. GHRH (both cAMP and IP3/DAG)
  4. angiotensin II
  5. ADH (v1)
  6. oxytocin
  7. alpha 1 receptors
54
Q

which hormones use steroid hormone mechanism?

A
  1. glucocorticoids
  2. estrogen
  3. progesterone
  4. testosterone
  5. aldosterone
  6. 1-25 dihydroxycholecalciferol
  7. thyroid hormones
55
Q

what hormones use tyrosine kinase mechanism?

A
  1. insulin

2. IGF-1

56
Q

what hormones use cGMP

A
  1. ANP
  2. endothelial derived relaxing factor
  3. NO
57
Q

when is prolactin released?

A

all during the night

58
Q

what stimulates prolactin

A

pregnancy, estrogen, nursing, TRH (pharmacological dose), dopamine antagonist

**no true hypothalamic stimulator of prolactin

59
Q

what inhibits prolactin

A

dopamine (PIH), dopamine agonists, GHIH, GnRH associated peptide (GAP), prolactin

60
Q

what does dopamine do with prolactin

A

lowers cAMP and Calcium

61
Q

how is prolactin regulated

A

prolactin directly stimulates release of dopamine from hypothalamus which inhibits its release from AP.
TRH positively affects prolactin release.

62
Q

trace the stimulus of suckling to lactation

A
  1. suckling starts. is sensed.
  2. sensory info sent to hypothalamus
  3. hypothalamus releases oxytocin to PP, prolactin to AP.
  4. oxytocin causes milk ejection
  5. prolactin causes milk production
63
Q

how does prolactin cause milk production

A

binds to receptor that causes cytoplasmic tyrosine kinase chain. impacts mRNA synthesis that makes enzymes for lactose synthesis, enzymes for lipid synthesis, and casein.

64
Q

describe hyposecretion of prolactin

A

hypolactogenesis

difficulty producing milk

65
Q

what happens in hypersecretion of prolactin

A
  1. amenorrhea
  2. galactorrhea (milk flow not associated with childbirth/nursing)
  3. witch’s milk - milk excreted from infant
66
Q

what could cause galactorrhea?

A

elevated TSH or TRH

Medical Physiology (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions