Sex Hormones

Question 1

What are the 3 main sex hormones and which receptors do they act on

Answer 1

Oestrogen

Progesterone

Androgen/testosterone

Act nuclear hormone dep receptors (which recruit rna pol)

Question 2

Which 2 cycles are included in the menstrual cycle

Answer 2

Ovarian cycle (dev of follicles and release)

Uterine cycle (growth of endometrium)

Question 3

How is oestrogen important in menstrual cycle / fertility

Answer 3

It causes development of follicles

Allows build up of endometrium for fertilised egg

Allows uterine contraction

Question 4

How is oestrogen important for lactation

Answer 4

Duct growth

Inhibition of prolactin

Question 5

How does oestrogen make people gain weight

Answer 5

It is anabolic, builds fat muscle and skin

Question 6

When does progesterone become important

Answer 6

After ovulation to maintain the emdometrium

Question 7

What does endometrium receptivity mean via progesterone

Answer 7

Ability for blastocyst / ovum to attach to it when fertilised

Question 8

Does progesterone also allow lactation

Answer 8

Yes (also via inhibiting prolactin)

Question 9

What is the disorder without progesterone called causing infertility

Answer 9

PMS

Question 10

Which hormonal axis is involved in menstrual cycle

Answer 10

HPO (hypothalmic, pituitary, ovary axis)

Question 11

Which hormone triggers release of LH and FSH from anterior pituitary

Answer 11

Gonadotropin RH

Question 12

Which nucleus produces Gonadotropin RH

Answer 12

Arcuate nucleus

Question 13

Which sex hormone does fsh release allow production of

Answer 13

Oestrogen

Question 14

Where does fsh bind to to produce oestrogen

Answer 14

Granulosa cells on Graafian follicle

Question 15

Where does Lh bind

Answer 15

Corpus luteum ( differentiated granulosa and the cal cells)

Question 16

What happens when LH binds to corpus luteum/granulosa and theca

Answer 16

Production of progesterone

And stimulation of oestrogen

Question 17

Why is it important for the LH to stimulate the progesterone and oestrogen in the luteal phase

Answer 17

To thicken the endometrium ready for fertilised egg

Question 18

What negative feedbacks to stop fsh production

Answer 18

Production of too much oestrogen

Question 19

What things does Progesterone increase and oestrogen in luteal phase NF to

Answer 19

Stop GnRH, fsh and LH (stop follicular maturation and ovulation)

Question 20

How is progesterone produced

Answer 20

When LH binds to corpus luteum / the cal cells and causes a cascade to convert cholesterol to progesterone

Question 21

What is progesterone metabolised into

Answer 21

Testosterone

Question 22

What happens when fsh binds to granulosa cells

Answer 22

Production of oestrogen from testosterone from the cal cells

Via aromatase induction

Question 23

Why is fsh high at the start of menstrual cycle

Answer 23

Because oestrogen was decreased when sperm wasn’t present causing feedback to release FSH

Question 24

Why is it important for fsh to be high at follicular phase

Answer 24

Binds to granulosa and oestrogen is produced from testosterone via aromatase

Oestrogen needed for maturation of follicle

Question 25

Apart from maturation of follicle was does high oestrogen allow

Answer 25

Proliferation of endometrium

Question 26

When is there an LH surge

Answer 26

At ovulation day 14 to cause release of oocyte

Question 27

What peaks in the luteal phase for continued development of endometrium and holding of corpus luteum

Answer 27

Progesterone and oestrogen

Question 28

Which hormone is needed to prevent regression of corpus luteum into albicans

Answer 28

HCG

Question 29

What would happen if no HCG present

Answer 29

Progesterone and oestrogen can’t be maintained in corpus luteum Period begins (breakdown of endometrium) LH and FSH start to increase again

Question 30

What substance thickens for sperm passage when pregnant due to progesterone

Answer 30

Mucus

Question 31

Which types of receptor agonists would stop follicular maturation and ovulation via fsh and LH decrease

Answer 31

Oestrogen and progesterone receptor agonists

Question 32

How does the combination pill work

Answer 32

Oestrogen receptor agonist —- blocks release of fsh = no maturation Progesterone receptor agonist —— blocks fsh and LH LH inhibition would stop ovulation day 14

Question 33

What do progesterone agonists also do to stop sperm

Answer 33

Build mucus even more

Question 34

Why would combination pill make you fat

Answer 34

Oestrogenic receptor agonist effects Anabolic build up of fat

Question 35

Why would oestrogen receptor agonists cause thromboembolic disease like DVT

Answer 35

Too much prothrombin production into thrombin via oestrogen stimulation

Question 36

How does the emergency contraceptive pill work

Answer 36

Progesterone receptor antagonist Would break down the endometrium and stop mucus production so not stable for fertilisation

Question 37

Why are ER and PR agonists important for menopause replacement therapy

Answer 37

Follicular cells in menopause decrease Also oestrogen lacks in menopause so it’s a replacement to cause maturation

Question 38

What is an issue with HRT for menopause

Answer 38

It increase ER and PR which stop the actual ovulation of the egg via LH inhibition

Question 39

How is ovulation induced

Answer 39

Via fsh and LH agonists

Question 40

How can ER partial agonists stimulate ovulation

Answer 40

By allowing early maturation

Question 41

Which 2 types of drugs are given for anti cancer

Answer 41

ER antagonists ER partial agonists (SERM) eg tamoxifen

Question 42

How can hormone antagonists for cancer work eg er antagonists

Answer 42

Blocking their receptors Or blocking production eg via aromatase blockage

Question 43

How is a serm partial antagonist like tamoxifen stopping cell proliferation

Answer 43

It binds to the nuclear hormone receptor and when receptor binds to dna it is unstable so can’t recruit rna polymerase No proteins are translated so no cell proliferation