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Flashcards in Hypothalamic Pituitary Relationships Deck (85)
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1

The communications between the hypothalamus and ________ _____ are neural and hormonal

Anterior pituitary

2

Hormones of anterior pituitary

ACTH
TSH
FSH
LH
GH
Prolactin

3

What is a hallmark symptom of pituitary tumors?

Vision changes d/t impingement of optic chiasm and optic n

4

What is the direct route of delivery of hormones from the hypothalamus to the anterior pituitary?

Hypothalamic hypophysial portal system

5

T/F: Hormones from the anterior pituitary appear in high concentrations in systemic circulation

False; they have high concentration within the gland itself

6

The anterior pituitary has neural and hormonal signals with the hypothalamus. The posterior pituitary has ____ signals only

Neural

7

The anterior pituitary is a collection of endocrine cells; the posterior pituitary is a collection of ______ whose cell bodies are located in the hypothalamus

Axons

8

The cell bodies in the hypothalamus that communicate with the posterior pituitary are associated with what 2 nuclei? What neuropeptides do they secrete?

Supraoptic nucleus (SON) = secretes ADH

Paraventricular nucleus (PVN) = secretes oxytocin

9

Compare/contrast primary vs. secondary vs. tertiary endocrine disorders

Primary = at the level of peripheral gland

Secondary = problem with pituitary

Tertiary = problem with hypothalamus

10

Hormone families of the anterior pituitary are organized by structural and functional homology. What are the 3 families of the anterior pituitary?

ACTH family = corticotrophs; secrete ACTH

TSH, FSH, LH family = thyrotrophs (secrete TSH); gonadotrophs (secrete FSH and LH)

GH, Prolactin family = somatotrophs (secrete GH), lactotrophs (secrete prolactin)

11

Match the releasing hormone with its target in anterior pituitary and hormone secreted:

TRH

Thyrotrophs —> TSH

12

Match the releasing hormone with its target in anterior pituitary and hormone secreted:

CRF

Corticotrophs —> ACTH

13

Match the releasing hormone with its target in anterior pituitary and hormone secreted:

GnRH

Gonadotrophs —> LH, FSH

14

Match the releasing hormone with its target in anterior pituitary and hormone secreted:

GHRH vs. somatostatin

GHRH —> somatotrophs —> GH

Somatostatin inhibits somatotrophs secretion of GH

15

PIF (dopamine) from hypothalamus acts on ______ in anterior pituitary to inhibit secretion of _____

Lactotrophs; PRL

16

Activity of endocrine axes are maintained at a set point, often secreting hormones in pulsatile manner and entrained to circadian rhythms. What are the axes associated with the anterior pituitary gland?

Hypothalamic-Pituitary-Gonad (HPG)

Hypothalamic-Pituitary-Liver

Hypothalamic-Pituitary-Prolactin

Hypothalamic-Pituitary-testis/ovary

Hypothalamic-Pituitary-thyroid

Hypothalamic-Pituitary-Adrenal

17

Rare disease characterized by excessive growth of soft tissue, cartilage, and bone in the face, hands, and feet; caused by prolonged and excessive secretion of growth hormone in adult life

Acromegaly

18

Physical findings of acromegaly

Prominent supraorbital ridges
Lower teeth separation
Prominent lower jaw
Cardiomegaly
Organomegaly
Hyperglycemia
Enlarged head circumference
Hypertension
Large hands
Accelerated osteoarthrosis
Increased heel-pad thickness on x-ray
Large feet

19

Growth hormone is produced by somatotropes

It targets _____ and ______ (organs)

The GH receptor is linked to _______ signaling

Liver; bone

Jak-stat

20

Growth hormone is inhibited by ____ and _____ as part of a negative feedback mechanism

Somatostatin (GHIH)

IGF-1

21

What are the 2 primary stimulators of GH secretion?

Fasting/hunger/starvation

Hypoglycemia

[also puberty hormones, exercise, sleep, and stress]

22

GH binds directly to target cells in ____ and ____

Bones; muscle

23

GH binds directly to bones and muscle. What effect does it have on growth?

Hypertrophy - increase in size/volume of cells (ex: increases bone thickness)

24

GH binds directly to bones and muscle. What effect does it have on cell reproduction?

Hyperplasia = increase number of cells or proliferation rate via mitosis (ex: increase bone length)

25

GH binds directly to bones and muscle. What effect does it have on metabolism?

Increase glycogen and fat breakdown for energy to increase protein synthesis

26

Another name for growth hormone

Somatotropin

27

Another name for insulin-like growth factor 1 (IGF-1)

Somatomedin C

28

In a normal hypothalamic-pituitary-growth hormone axis, the hypothalamus releases either ______ and ______, or ______, which act at the anterior pituitary which will either be stimulated or inhibited to release growth hormone.

Two of the above will stimulate the release of growth hormone, which proceeds to the ______ which releases _______

Ghrelin; GHRH; somatostatin

Liver; IGF-1

29

Describe a primary GH insensitivity in terms of the HPGh axis

The liver is insensitive to GH, so GH levels rise

30

Describe a secondary GH insensitivity in terms of the HPGh axis

Secondary = problem with pituitary

Ghrelin and GHRH or somatostatin are released from hypothalamus, but GH cannot be released from anterior pituitary. IGF-1 does not get stimulated at all. GH levels are LOW