Physiology of Female Reproductive System Flashcards Preview

SF3-EXAM 4 (CAMELITA) > Physiology of Female Reproductive System > Flashcards

Flashcards in Physiology of Female Reproductive System Deck (55)
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1
Q

Follicular structures

A

Premodial follicle-> Primary follicle-> Secondary follicle-> Graafian follicle

2
Q

Of the two layers of theca cells, which makes the most hormones?

A

Theca interna

3
Q

Progesterone is made from which cells?

A

Granulosa lutein cells

4
Q

When is the corpus luteum formed?

A

After ovulation

  • The antum collapses, granulosa cells becomes granulosa lutein cells and theca cells become theca lutein cells

NOTE: The follicular fluid contains a lutenization inhibitor which inhibits most of the the luteinization before the ovulation. Once the cell loses follicular fluid, we lose inhibition of the conversion of the luteinization state.

5
Q

What are the two phases of follicular growth?

A
  • Stimulated
    • Regulated by gonadotropins and terminates in atresia or ovulation.
  • Tonic or Basal
    • Before LH and FSH appear

NOTE: Each month about 100 follicle begin stimulate growth with 20 reaching a larger size

6
Q

What are the major characteristics of the early follicular growth phase?

A
  • Rising GnRH leads to increased FSH and LH
  • Increased FSH leads to increased follicular growth, aromatase, LDL and LH receptor
    • NOTE: We get 30% of cholesterol from plasma LDL
  • Increased LH leads to increased androgen production and vasculatization of the theca interna region
7
Q

What are the major characteristics of the late follicular growth phase?

A
  • LH acts on granulosa and thecal cells, FSH acts on granulosa cells
  • Follicular fluid characterized by elevated levels of estradiol, progestins, LH and FSH but low androgens
  • Atretic follicles charachterized by elevated androgen levels
8
Q

Aromatase is an important enzyme in ______ synthesis.

A

Estrogen

9
Q

Elevated levels of ____ can be expected when we stop making P450 aromatase.

A

Androgens because we stop converting androgens to estrogens.

10
Q

Ovarian steroid synthesis

A
11
Q

When we stimulate the follicle with LH, it stimulates the induction of more ______ protein into the mitochondria membrane.

A

StAR

NOTE: Cholesterol cross the mitochondria membrane via the StAR protein. Once in the mitochondria, cholesterol is converted to pregenelone via the P450 side chain cleavage enzyme.

12
Q

What are the two hormones that can be converted to estradiol?

A

Estrone and testosterone

NOTE: Cholesterol-> Pregenolone-> Progesterone-> 17-hydroxyprogesterone-> androstenedione->estrone-> ESTRADIOL

-OR-

Cholesterol-> Pregenolone-> Progesterone-> 17-hydroxyprogesterone-> androstenedione-> testosterone-> ESTRADIOL

13
Q

Which two cell types are required for the synthesis of follicular estrogen?

A

Theca cells

  • Synthesize androgens
  • Stimulated by LH
    • Leads to induction of enzymes needed for andostenedione synthesis
      • Andostenedione diffuses into the granulosa cell

Granulosa Cells

  • Convert androgens to estrogens
  • Stimulated by FSH
    • Leads to induction of P450 aromatase
14
Q

What is the role of SF1?

A

SF1 is a nuclear receptor that stimulates StAR in mitochondria membrane

15
Q

__________is a preadipocyte-specific nuclear receptor that regulates expression of aromatase in adipose tissue.

A

LRH-1

16
Q

The _________, a cone shaped protrusion of the follicular wall, appears just prior to ovulation.

A

Stigmata

17
Q

What events take place right before ovulation?

A
  • Appearance of stigmata
  • Follicular fluid has elevated estrogen, prohgestins, FSH, LH, oxytocin, plasmin and collagenase activity
    • Plamin degrades the basal lamina
    • Collagenase cleaves adhesive proteins
  • Extensive vascularization

NOTE: These events help to weaken the follicle and prepare it for ovulation.

18
Q

Myoepithelial cells located around the basal lamina are stimulated by ________.

A

Oxytocin

NOTE: Oxytocin promotes contractions and it builds up in the follicular fluid prior to ovulation.

19
Q

If we properly weaken the area of the stigmata, we then eject an oocyte with cumulus complex, freeing it from the rest of the follicle. The rest of the follicle becomes the _________.

A

Corpus luteum

20
Q

Which enzymes serve to digest the follicular wall and weaken granulosa cell adhesion?

A
  • Collagenase
  • Plasmin

NOTE: The wall gives way at the weakened area forming the stigmata

21
Q

What are the 3 phases of corpus luteum development?

A
  • Early luteal phase
  • Advanced Luteal Phase
  • Late Luteal Phase

NOTE: FSH has no direct role in corpus luteum maintenance

22
Q

What occurs during the early luteal phase?

A
  • LH stimulates thecal and granulosa cell growth
  • LH induces luteinization of both cell types and subsequent growth of luteinized cells
  • Progesterone synthesis increases as the number of luteal cells increase
23
Q

What occurs during the advanced luteal phase?

A
  • LH stimulates increased estrogen and progesterone synthesis
  • Corpus luteum function depends on adequacy of follicular development before ovulation
    • FSH induction of adequate LDL receptor and LH receptor levels before ovulation assures sufficient steroidogenesis by the corpus luteum
    • Inadequate CL production of progesterone leads to luteal insufficiency

NOTE: FSH has no direct role in corpus luteum maintenance

24
Q

What occurs during the late luteal phase?

A
  • Estrogen enduces luteolysis
    • ​Luteolysis leads to decreased plasma progesterone and estrogen
    • Luteolusis process continues in absence of fertilized ovum
25
Q

What is different about steroid synthesis in the follicular phase and steroid synthesis in the luteal phase?

A

Follicular phase

  • Granulosa cells stimulated by FSH

Luteal phase

  • Granulosa cells stimulated by LH
26
Q

Inhibin, activin, and follistatin are secreted by the ____ of the testes and the ______ cells of the ovaries.

A

Sertoli; granulosa

27
Q

Inhibin

A

Feedback from gonads to the anterior pituatary and suppress secretion of FSH

28
Q

Activin ________ (stimulates/inhibits) FSH secretion.

A

Stimulates

29
Q

Folistatin binds to ____ and blocks its activity on pituatary gonadotropes to reduce FSH secretion.

A

Activin

30
Q

Which estrogen type has the most estrogenic activity?

A

E2- 17 betaestradiol

31
Q

What affect does estrogen have on the ovaries?

A

Increase function

32
Q

What effect does estrogen have on the uterus?

A
  • Increased growth
  • Increased endometrial growth
33
Q

What effect does estrogen have on the fallopian tubes?

A
  • Increases overall growth
  • Increases mucosal growth
34
Q

What effect does estrogen have on the breasts?

A
  • Increases growth and development
  • Increased fat deposition
  • Increased stromal cell growth
  • Increased ductile system development

NOTE: Estrogen increases growth and progestorone increases secretion

35
Q

What are the phases of the uterine cycle?

A

Proliferative phase

  • ​Growth of stromal and epithelial cells as well as blood vessels
    • Via estrogen produces

Secretory phase

  • Glands become convoluted, secretion greatly increases, growth continues.
  • Estrogen and progesterone are being produced
36
Q

What are the stages of the cervical cycle?

A
  • Early follicular cycle
    • Low mucus volume and elasticity, high viscosity
  • Late follicular phase
    • Increased mucus volume and elasticity, decreased viscosity
  • Luteal phase
    • Similar to that of the early follicular phase
    • Progesterone blocks the activity of estrogen
37
Q

What are the two kinds of secretion of the cervix?

A

Surface mucus cells

  • Make a really thick mucus
  • Prevents things from goin gin and out

Endometrial glands

  • Makes a thin high protein secretion
    • High protein leds to elasticity
    • Allows spermatozoa to go in

NOTE: Estrogen stimulates cervical gland secretion

38
Q

Follicular phase in ovary= __________ phase in uterus.

A

Proliferative

39
Q

Luteal phase in ovary= __________ phase in uterus.

A

Secretory phase

40
Q

What are the phases of the vaginal cycle?

A

Early follicular

  • Predominenately basophilic cells
  • Decreased volume; increased viscosity

Late follicular

  • Predominately cornified cells
  • Increased volume, decreased viscocity

Luteal

  • Decreased cornified cells, increased polymorphonuclear neutrophils
  • Decreased volume, increased viscocity
41
Q

What are the phases of the adult menstrual cycle?

A

Follicular phase

  • Post-mentrual, proliferative, estrogenic
  • Follicular maturation
  • Proliferative endometrium

Luteal phase

  • Premenstrual, secretory, progestational
  • Corpus Luteum Activity
  • Secretory endometrium
42
Q

Rise in basal body temperature is induced by _______.

A

Progesterone

43
Q

Estrogen peak in the follicular phase is the result of a switch to ___________ feedback regulation of the gonadotropins.

A

Positive

44
Q

Inhibin B is produced mainly by the ___________, while inhibin A is derived mainly from the __________.

A

Follicle; Corpus luteum

The B version inhibits FSH

45
Q

The major androgen from thecal cells is __________.

A

Androstenedione

46
Q

What accounts for the LH surge?

A

Positive feedback regulation from LH and FSH, stimulate the hypothalamus to release GnRH, which stimulates LH release.

NOTE: FSH is inhibited by inhibin B, which is why there is no FSH surge to accompany the LH surge

47
Q

A ________ secretion of GnRH is required to stimulate pituatary secretion of gonadotropins.

A

pulsitile

NOTE: If we give the pituatary a tonic signal, it shuts down and stops secreting.

48
Q

What are the three patterns of gonadotropin secretion in women?

A

Chichoral

  • High frequency changes occuring at 1-5 hour intervals

Diurnal

  • Intermittent frequency changes occuring across a 24-hr period

Trigintan

  • Low frequency changes occuring across a 29-30 day period
49
Q

Estrogen feedback supresses the ______ (amplitude/frequency) of gonadotropin pulses. Progesterone feedback supresses the _______ (amplitude/frequency) of gonadotropin pulses.

A

Amplitude; frequency

50
Q

What levels of estrogen trigger a switch to positive feedback control?

A

>300 pg/ml for >24 hours

51
Q

What are the major types of oral contreceptives?

A

Estrogen-progesterone

  • Suppresses ovulation and supports secondary sex organ function
  • Used to regularize cells in some subjects

Progesterone mini pill

  • Blocks estrogen induced cervical mucus changes

The estrogen “morning after” pill

  • A high dose estrogen treatment
  • Believed to function by interfering with implantation
    • It is believed that the implantation site is chosen by the level of estrogen at the site

NOTE: Oral contraceptives suppres the cyclical pattern of all major reproductive hormones

52
Q

Addition of _________ increases plasma half-life of oral contreceptives.

A

Ethinyl group

53
Q

Non-oral contraceptives

A

Progestin Type

–Injection

  • Depo-provera (methoxy progesterone)
    • Effective for three months

–Implant

  • Norplant (levo norgestrel)
    • Effective for up to five years
54
Q

Effects of oocyte aging

A
  • Increased incidence of birth defects
    • Increased downs syndrome
    • Increased Klinefelters Syndrome
  • Increased incidence of spontaneous abortion
55
Q

What is the main cause of hirsutism?

A

Main cause is increased ovarian and/or adrenal androgen secretion

*Can be exacerbated by TeBG responses