Hypothalamic and Pituitary relations part 1

Question 1

What connects the hypothalamus to the pituitary gland?

Answer 1

Hypophysial stalk (infundibulum)

Question 2

What type of connection does the hypothalamus have to the posterior pituitary gland?

Answer 2

Neural signal

Question 3

What type of connection does the hypothalamus have to the anterior pituitary gland?

Answer 3

Neural and hormonal (endocrine) signals

Question 4

Another name for the pituitary gland

Answer 4

Hypophysis

Question 5

What are the initial signs of a pituitary gland tumor?

Answer 5

Dizziness and visual problems because it compresses the optic nerves

Question 6

What are the nuclei in the hypothalamus that send axons to the posterior pituitary?

Answer 6

Supraoptic and paraventricular nuclei

Question 7

What do the supraoptic and paraventricular nuclei in the hypothalamus send down their axons to the posterior pituitary for it to release?

Answer 7

ADH and Oxytocin

Question 8

What do the hypothalamic neurons use to send releasing-hormones or release-inhibiting hormones to the anterior pituitary?

Answer 8

Hypothalamic-hypophysial portal vessels (blood)

Question 9

Once the releasing hormones or release-inhibiting hormones reach the anterior pituitary, what do they do?

Answer 9

They either stimulate or inhibit the release of anterior pituitary hormones

Question 10

Corticotrophs

Answer 10

ACTH

Question 11

Thyrotrophs

Answer 11

TSH

Question 12

Gonadotrophs

Answer 12

FSH and LH

Question 13

Somatotrophs

Answer 13

GH

Question 14

Lactotrophs

Answer 14

Prolactin

Question 15

Primary endocrine disorders affect?

Answer 15

Peripheral gland

Question 16

Secondary endocrine disorders affect?

Answer 16

Pituitary gland

Question 17

Tertiary endocrine disorders affect?

Answer 17

Hypothalamus

Question 18

HPG axis

Answer 18

Hypothalamic-pituitary-Gonadal axis

Question 19

What does the hypothalamus release to the anterior pituitary for the HPG axis?

Answer 19

GnRH

Question 20

What does the anterior pituitary release to the testes for the HPG axis?

Answer 20

LH and FSH

Question 21

For the HPG axis for Testes, LH stimulates _____ to release _____

Answer 21

Leydig cells to release Testosterone

Question 22

For the HPG axis for Testes, FSH stimulates ______ to perform _________

Answer 22

Sertoli cells to perform spermatogenesis

Question 23

What can sertoli cells produce to inhibit FSH release from the anterior pituitary?

Answer 23

Inhibin

Question 24

Testosterone has a negative feedback loop at what locations?

Answer 24

Anterior pituitary (LH) and Hypothalamus (GnRH)

Question 25

For the HPG axis for Ovaries, LH stimulates ____ to release _____

Answer 25

Theca cells to release Androgens

Question 26

For the HPG axis for Ovaries, FSH stimulates ______ to release ______

Answer 26

Granulosa cells to release progestins and estrogens

Question 27

What can granulosa cells produce to inhibit FSH release from the anterior pituitary?

Answer 27

Inhibin

Question 28

For the negative feedback pathway in the Ovaries, what can have a negative feedback loop at what locations?

Answer 28

Progestins and Estrogens can have a negative feedback loop at the Anterior pituitary and at the Hypothalamus levels

Question 29

Leydig cells and Theca cells activate or release androgens that do what?

Answer 29

Stimulate the roles of the Sertoli cells and the Granulosa cells

Question 30

For the GH axis, what does the Hypothalamus release?

Answer 30

``` Either GHRH (growth hormone releasing hormone) OR GHIH (growth hormone inhibiting hormone) ```

Question 31

Once the hypothalamus releases GHRH to the anterior pituitary it releases GH to where?

Answer 31

Either directly to the bones and soft tissue or to the liver

Question 32

What does the liver release in response to GH?

Answer 32

IGF-1

Question 33

What does IGF-1 do?

Answer 33

Stimulates growth of bone and soft tissue

Question 34

What types of feedback does IGF-1 contain?

Answer 34

(+) stimulates GHIH which then inhibits GH release | (-) inhibits GH release directly at anterior pituitary

Question 35

GH has negative feedback where?

Answer 35

At the hypothalamus to inhibit GHRH

Question 36

GH secretion fluctuates throughout the day, when is it at its highest?

Answer 36

During sleep and during exercise

Question 37

GH secretion fluctuates throughout a lifetime, describe it.

Answer 37

GH secretion increases until it reaches a peak during puberty and then slowly declines with old age

Question 38

What can excessive GH lead to?

Answer 38

Gigantism or acromegaly

Question 39

Excessive GH BEFORE closure of bone epiphyses

Answer 39

Gigantism

Question 40

Excessive GH AFTER closure of bone epiphyses

Answer 40

Acromegaly

Question 41

What is acromegaly?

Answer 41

Excessive growth of soft tissue - large hand, large feet, large head -- cartilagenous tissues

Question 42

INCREASED GH released from anterior pituitary due to decreased or lost IGF-1 feedback

Answer 42

Primary GH deficiency because it affects the liver

Question 43

DECREASED GH released from anterior pituitary

Answer 43

Secondary GH deficiency

Question 44

DECREASED GHRH released from hypothalamus

Answer 44

Tertiary GH deficiency

Question 45

Increased carb intake and increased protein intake does what to the GH axis?

Answer 45

Liver produces IGF-1 for growth

Question 46

Increased carb intake and decreased protein intake does what to the GH axis?

Answer 46

Inhibits GH and Liver will NOT produce IGF-1 and this results in weight gain

Question 47

Decreased carb intake and increased protein intake does what to the GH axis?

Answer 47

Produces lots of GH and promotes lipolysis yet, insulin insensitivity

Question 48

When the hypothalamus releases dopamine to the anterior pituitary what does it do?

Answer 48

It inhibits the anterior pituitary and allows release of Prolactin

Question 49

Prolactin is increased with pregnancy and can negatively inhibit what?

Answer 49

GnRH in order to stop menstrual cycles

Question 50

How is oxytocin packaged?

Answer 50

Prepro-oxyphysin is put into vesicles as pro-oxyphysin in the hypothalamus and is then sent to the posterior pituitary to be released as Oxytocin

Question 51

What are the main actions of oxytocin?

Answer 51

Milk letdown for breast feeding and Uterine contraction during childbirth