Folliculogenesis (2)

(mural) granulosa cells

The ….. are the ones that would producing estrogen 

cumulus granulosa cells

The ….. are going to be the one that provides the inhibition to the oocyte

testosterone

The theca cells would produce …. which would then transition to the granulosa cells (mural) to produce estrogen 

follicular fluid

The …. is going to be a reservoir for nutrients, hormones, growth factors, and communication (through mural granulosa cells)

paracrine signaling

There would be ….. that occurs between the adjacent(mural) granulosa and theca cells 

granulosa cells 

From the anterior pituitary, FSH would bind to the FSH receptor in the ….

theca cells

From the anterior pituitary, LH would bind to the LH receptor on the …

pregnetalone

In the theca cells, cholesterol would travel to the mitochondria to be convert into …., then progesterone, and then goes all the way down to produce testosterone 

substrate

The testosterone is a …. to go from the theca cells into the granulosa cells 

enzyme aromatase

In the (mural) granulosa cells, it goes through a similar process and ultimately we have an increase in the …. which allows the conversion of testosterone into estrogen  

very small follicle

A …. would be more dependent on FSH. As it grows and develops, it would be more dependent on LH

follicular rupture

Hormones in the follicular fluid would aid in … and growth and development of the cells 

communication

The role of the follicular fluid is to support the growth of the follicle and aiding …. 

recruitment

In stages of follicular growth, the first stage is ….. This is where a large number of follicles being recruited and there is relatively small concentrations of estrogen being produced 

selection

The next step is ….. It is like a refinement process. There is a large number of follicles that make it into the anthro follicles that are being recruited and many would go under a process called atresia (death). So we lose gametes meaning that we decrease the number of follicles that make it to this stage but then we increase the size of the follicles and now more estrogen is being produced 

atresia

Cell death

dominance

The last stage is called ….. We continue to decrease the number of follicles (cattle and mares) and have one dominant follicle. There is a huge increase in estrogen concentrations and we see the follicle reach it’s maximum size

gonadotropin support

The selection process is done through … (LH and FSH) 

waves

Follicles grow in a series of … and the numbers change as well

growth factors

Follicular development is going to be regulated by … and gonadotropins 

activin and inhibin

The large follicle (specifically the granulosa cells) are going to produce the 2 hormones ….

FSH

Both go directly to the anterior pituitary and they regulate …

Activin

… is going to be produced by the very small follicles to increase follicle stimulating hormone 

Inhibin

… is going to be produced by the large follicles to inhibit FSH

ovary

These are ways to regulate what is present in the … 

low

A fate of a follicle: If they have a large dominant follicle on the ovary, then it has the opportunity to ovulate and progesterone must be …. and in the right stage of estrus for that to occur

follicular death 

A fate of a follicle: Most follicles would undergo ….

cystic

A fate of a follicle: They can become … where the follicles (because of a disease situation…maybe) would not listen to the rest of the body

high

If progesterone levels are …, then the dominate follicle is going to undergo atresia and a new wave would begin (recruitment, selection, dominant)

ovulatory and non-ovulatory period

The waves of follicular growth occurs in …

Non-ovulatory

Progesterone is going to be blocked the surge center, which then blocks the LH surge 

dominant or subordinate 

Follicles during growth would be considered …

dominant follicle

If progesterone is high, then the … goes into atresia and die

first wave

The …. (after ovulation occurs): Follicles would go through recruitment, selection, and then there is a dominant follicle. But because progesterone is high, it goes through atresia and dies

non obligatory wave

The first follicular wave after ovulation is a …

recruitment follicles

After the death of the dominant follicle, …. grows in its place which means this is another wave and the process occurs again

die

But because the progesterone is still high, the dominant follicle would ….

surge center

This second wave is still a non-oblatory wave because progesterone is going to block the ….

LH and FSH

… allows the follicle to grow and develop 

pre-oblitory follicle

In wave 3 (could be cows), the process returns (recruitment, selection, and dominant). But progesterone levels are decreasing so that gives the dominant follicle the opportunity to become the …, remove the inhibition. This is because luteolysis occurred, causing progesterone levels to decrease. Which then allows the surge center to activate the estrogen that the large dominant follicle produced which allows the LH surge to occur which then allows for ovulation

negative effect

The dominant follicle could have a …. on the subordinate follicles by preventing the other follicles from growing and developing due to its size 

dominant follicle

The … also consumes most of the gonadotropins and produces more inhibin which causes less FSH to be produced

Recruitment

More (max) FSH and less (min) LH as well as less estrogen being transferred from the follicles to the surge center

Selection

A bit less FSH and a bit more LH as well as a bit more estrogen. Inhibin would also be coming from the granulosa cells and travel to the anterior pituitary 

Dominant

More LH (max) and less FSH (min) as well as MORE estrogen. MUCH more inhibin as well 

FSH

If we want to keep the number (a lot) of recruited follicles alive, we provide more ….

luteinization

In ovulation, the cumulus oocyte complex is expelled. Those cells that remains (theca and granulosa cells) undergo the terminal differentiation called …. (the beginning of the formation of the CL)

surge of LH

The …. triggers ovulation 

increases

In ovulation, FSH … 

degradation

In ovulation, in order to expel the complex/oocyte, there has to be …. of the follicle wall and pressure. 

CL

After the oocyte is expelled, it would go though meiosis and then the collapsing of the follicle would become the ….

prostaglandin E2

The 2 mechanisms that causes the degradation of the wall and pressure is the increase of ….., (a vasodilator, it increases the fluid and causes edema surrounding the follicle which increases pressure)

ovarian prostaglandin F2 alpha

The other is an increase in …. (causes smooth muscle contractions within the ovary which increases pressure)

lysosomal enzymes

The ovarian prostaglandin F2 alpha would also release ….. These would start to chew away at the follicular wall 

progesterone

After the LH surge, there is an increase in ….. from the granulosa and theca cells 

collagenase

This increase in progesterone would also increase …. (this breaks the extra cellular matrix and helps weaken the follicular wall) 

changes

Oocytes are dormant in meiosis 1 while … occur to the surrounding cells

Primordial follicles

Single layer of squamous epithelial cells - Resting state - cues to grow

Primary follicle

Single layer follicle cells - Primary oocyte but starts to expand - Follicle cells expand (cuboidal) - Zona pellucida forms

Secondary follicle

Primary oocyte - Multiple layers of granulosa cells - Thecal layer forms - Pre-antral

Folliculogenesis

Classification and regulation of follicle growth

Parts of the follicle

Granulosa cells - Thecal cells - Follicular fluid

Granulosa

From cortex - Responsive to FSH - Convert testosterone to estradiol

Theca

From stroma - Responsive to LH - Convert cholesterol to testosterone

Components of follicular fluid (antral follicles)

Hormones (steroids, gonadotropin, prostaglandins) - Proteins - Enzymes - Carbohydrates

Functions of follicular fluid (antral follicles)

Supports follicle growth - Aids in oocyte development and health - Mediates granulosa cell functions

Early antral (Tertiary)

Primary oocyte - Oocyte reaches maximum size - Granulosa cells expand - Antrum forms - Thecal layer more prominent (Interna and Externa )

Graanfian follicle (Preovulatory)

Last stage of tertiary follicle - Primary oocyte

Waves and numbers

How do follicles grow?

Gonadotropins - Growth factors - Activin or Inhibin

How are follicles stimulated/regulated by?

Ovulation or atresia

What are some fates of follicles?

Many

… follicles are recruited

Few

…. are selected

One

…. dominant follicle

Ovulatory and non-ovulatory

What is a wave of follicular growth?

Dominant and subordinant

What is another wave of follicular growth?

LH and FSH and Inhibin

What are their signals?

FSH

Granulosa cell mitosis - Increases LH receptors - Steroidogenesis - Effects preantral and antral follicles

LH

Steroidogenesis - Effect antral follicles - Surge starts ovulation - Resumption of meiosis (Oocyte)

Inhibit follicle growth

Presence of a dominant follicle - Inadequate production of gonadotropins - Steroids (estrogens and androgens) - Inhibin (Protein produced by follicles which inhibits other follicles from developing by decreasing FSH release)

LH surge

What stimulates ovulation?

cascade

Ovulation occurs in a specific …. of events

Degradation of follicle wall

What is the first event?

Extrusion of oocyte (Resumption of meiosis)

What is the second event?

Collapse of the follicle

Third?