L15: Hypothalamus & Pituary Gland

Question 1

Functions of the endocrine system

Answer 1

1) development
2) reproduction
3) metabolism
4) homeostasis

Question 2

How does the endocrine system work?

Answer 2

via messenger molecules (hormones)

Question 3

What can the endocrine alter by binding to specific hormone receptors?

Answer 3

Structure/activity of the target cell

e.g
stimulate DNA synthesis
affect transcription/translation of mRNA’s
affect channel proteins & enzymes

Question 4

How is the posterior pituitary formed?

Answer 4

Neuroendocrine organ that releases hormones oxytocin & vasopressin (ADH)

Question 5

What does oxytocin & ADH enter to reach target tissues?

Answer 5

Venous drainage

Question 6

OXYTOCIN
1) where is it made
2) where is it stored & released by
3) key roles

Answer 6

1) made in the brain
2) released into the blood stream by the pituitary gland
3) role in the female & male reproductive systems

Question 7

Where is the posterior pituitary derived from?

Answer 7

Down-growth of the diencephalon

Question 8

Is the posterior pituitary neuronal/ectodermal?

Answer 8

Neuronal

Question 9

Is the anterior pituitary neuronal/ectodermal?

Answer 9

Ectodermal

Question 10

Where is the anterior pituitary derived from?

Answer 10

Rathke’s pouch (an up-growth of the oral cavity)

Question 11

Where is neurons sent to from the hypothalamus?

Answer 11

Median eminence

Question 12

Where does neuropeptide hormones released at the median eminence enter?

Answer 12

Portal vessels

Question 13

How many hormones does the anterior pituitary secrete?

Answer 13

6

Question 14

What are the 6 hormones the anterior pituitary secretes?

Answer 14

1) Growth hormone (GH)
2) Follicle stimulating hormone (FSH)
3) Lutenising hormone (LH)
4) Adrenocorticotrophic hormone (ACTH)
5) Thyroid stimulating hormone (TSH)
6) Prolactin (PL)

Question 15

What are 4 releasing hormones of the hypothalamus that travel to the anterior pituitary?

Answer 15

1) Growth hormone releasing hormone (GHRH)
2) Corticotropin releasing hormone (CRH)
3) Thyrotropin-releasing horone (TRH)
4) Gonadotropin releasing hormone (GnRH)

Question 16

2 inhibiting hormones

Answer 16

1) somatostatin (SS)
2) dopamine (DA)

Question 17

Where is FSH/LH made?

Answer 17

Luteotrophs (gonadotrophs)

Question 18

What is FSH/LH released in response to?

Answer 18

Hypothalamic GnRH

Question 19

Functions of FSH/LH

Answer 19

Release of reproductive hormones
Production of gametes

Question 20

LOSS OF FSH/LH

Answer 20

• prevents puberty
• calorie restriction causing loss of reproductive function

Question 21

Function of adminstering GnRH when there is a loss of FSH/LH

Answer 21

manipulate reproduction

Question 22

Where is growth hormone made?

Answer 22

Somatotrophs

Question 23

What is secretion of GH inhibited by?

Answer 23

Hypothalamic SS

Question 24

What is GH released in response to?

Answer 24

Hypothalamic GHRH

Question 25

Functions of GH

Answer 25

Targets liver to produce somatomedins Stimulate growth in tissues

Question 26

What does lack of GH result in?

Answer 26

Short stature

Question 27

Where is TSH made?

Answer 27

Thyrotrophs

Question 28

What is TSH released in response to?

Answer 28

Hypothalamic TRH

Question 29

What does TSH act on the thyroid to generate?

Answer 29

Triiodothyronine (T3) & Thyroxine (T4)

Question 30

Role of prolactin

Answer 30

Stimulate reproductive function

Question 31

Where is prolactin made in?

Answer 31

Mammotrophs

Question 32

What is prolactin release inhibited by?

Answer 32

Hypothalamic dopamine

Question 33

What does prolactin stimulate in post-partum period?

Answer 33

Stimulates lactation

Question 34

What does oversecretion of prolactin leads to ?

Answer 34

Loss of reproductive function

Question 35

What produces & secretes ACTH?

Answer 35

Anterior pituitary gland (Corticotrophs)

Question 36

What is ACTH released in response to?

Answer 36

Hypothalamic CRH (corticotropin releasing hormone)

Question 37

WHat does ACTH act on the cortex of the adrenal gland to do?

Answer 37

Produce & release steroid hormones

Question 38

3 types of endocrine disorders

Answer 38

1) Excess secretion of a hormone 2) Deficient secretion of a hormone 3) Failure to respond to a hormone

Question 39

What is hormone secretion regulated by?

Answer 39

Feedback loops