7. Hypothalamic-pituitary hormones Flashcards Preview

Endocrine > 7. Hypothalamic-pituitary hormones > Flashcards

Flashcards in 7. Hypothalamic-pituitary hormones Deck (29):
1

CRH function

increases ACTH , MSH , β- endorphin secretion

2

CRH is decreased in ( situation )

chronic exogenous steroid use

3

Dopamine function ( hypothalamic pituitary )

decreases prolactin and TSH secretion

4

dopamine antagonist example

antipsychotics

5

dopamine antagonists can cause ( and why 0

glactorrhea due to hyperprolactinemia

6

GHRH function

increases GH secretion

7

GHRH analog ?
used for

tesmorelin
used to tread HIV lipodystrophy

8

GnRH function

increases the secretion of
1. FSH
2. LH

9

GnRH is regulated by

prolactin ( negative)

10

GnRH under tonic ( continous ) secretion

it supresses HPA axis

11

GnRH under pulsatile secretion

leads to puberty, fertility

12

prolactin effect on hypothalamic pituitary axon

it supresses GnRH secretion

13

pituitary prolactinoma - symptoms

1. amenorrhea
2. osteoporosis
3. hypogonadism ( infertility, low libido)
4. galactorrhea

14

TRH function

1. Increases TSH secretion
2. Increases prolactin secretion

15

prolactin secretion is regulated by

1. TRH (positively )
2. dopamine ( negatively)
3. prolactin ( negatively by increasing dopamin secretion)
4. estrpgem and progesterone ( positevely, in pregnancy)

16

somatostain analogs are used to

treat acromegaly

17

somatostatin function ( on hypothalamic pituitary axon )

decreases secretion
1. GH
2. TSH

18

TSH is regulated by

1. somatostatin ( negatively)
2. TRH (positevely)
3. T3/T4 ( negatively, decrease sensitivity of TRH)
4. dopamine ( negatively )

19

action of antipsychotics on hypothalamic pituitary axon

dopamine antagonists ( induce prolactin secretion)

20

TRH vs Dopamine according to their action on axon

-TRH increases TSH and prolactin
-Dopamine decreases TSH and prolactin

21

What is the effect of thyrotropin-releasing hormone (TRH) on pituitary hormone secretion?

Stimulates thyroid-stimulating hormone (TSH) and prolactin secretion

22

What is the effect of corticotropin-releasing hormone (CRH) on pituitary hormone secretion?

Stimulates secretion of adrenocorticotropic hormone (ACTH), melanocyte-stimulating hormone (MSH), and β-endorphin

23

A 10-year-old boy, short for his age, is found to have growth hormone (GH) deficiency. High/low levels of which hormone(s) may cause this?

Low growth hormone–releasing hormone (GHRH) or high somatostatin decreases the level of growth hormone

24

A 50-year-old man is found to have a somatostatin-producing tumor. How does this affect pituitary hormone secretion?

Inhibits growth hormone (GH) and thyroid-stimulating hormone (TSH) secretion

25

A woman with visual defects is found to have a prolactinoma. How does the high prolactin affect secretion of other pituitary hormones?

Inhibits gonadotropin-releasing hormone (GnRH), which in turn decreases luteinizing (LH) and follicle-stimulating hormone (FSH) secretion

26

A postpartum woman wants to breastfeed, requiring high prolactin. What must happen to dopamine levels to allow this?

Dopamine levels must decrease because dopamine has an inhibitory effect on prolactin release

27

A woman goes from taking a small amount of a GnRH agonist several times a day to taking large amounts a few times a day. What does this do?

Tonic GnRH administration suppresses the HPA axis, and switching to a pulsatile schedule promotes puberty and fertility

28

You give a patient a new drug to treat his HIV-associated lipodystrophy. GH level increases as a result. What is the mechanism of action?

Tesamorelin is a GHRH analog

29

A 20-y/o woman has had no menses for 3 months but has a white discharge from her nipples. What two hormones do you want to check?

α-hCG (for pregnancy) and prolactin (for possible prolactinoma, which can present with galactorrhea, amenorrhea, osteoporosis, hypogonadism)