EX 2; Reproductive Endocrinology Flashcards Preview

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Flashcards in EX 2; Reproductive Endocrinology Deck (87):
1

What are the three sex steroids secreted by the gonads

progestins
androgens
estrogens

2

What is the primary male hormone

testosterone, which is an androgen

3

Testosterone is more or less potent than DHEA or androgestenedione

more potent

4

What is the primary female hormone

estradiol, which is an estrogen

5

What is estrogen produced from

testosterone by an aromatase

6

This is the primary ovarian steroid during part of the menstrual cycle and during pregnancy

progesterone

7

This is secreted from pacemaker cells that produce bursts secretion is pulsatile

GnRH

8

gondaotropin (LH and FSH) secretion is pulsatile and results in what

pulsatile secretion of steroids

9

Continuous, non-pulsatile GnRH will inhibit what

FSH and LH secretion

10

which hormones have negative feedback on both GnRH and LH/FSH

gonadal hormones

11

positive feedback of this controls ovulation in females

estradiol

12

Which cells induce mitotically active spermatogonia and meiotic spermatocytes

spermatic cells (gametes)
produce 400 million sperm/day

13

These cells lie outside the seminifieroud tubules and synthesize T in response to LH actions of T

leydig cells

14

What is the role of Leydig cells in the gonad

regulate spermatogenesis

15

What is the role of Leydig cells elsewhere in the body besides the brain or gonads

produce secondary sex characteristics

16

What is the role of leydig cells in the brain

regulates sexual behavior
testosterone aromatizes into estrogen and sertoli cells to estradiol

17

These cells line the seminiferous tubule

sertoli cells

18

What is the role of sertoli cells in regulating spermatogenesis

regulate spermatogenesis in response to FSH

19

What is the role of sertoli cells in T sequestering

producing androgen binding proteins which sequesters T in the testis (so there is always enough T)

20

Sertoli cells secrete inhibin, which does what

its a peptide hormone that regulates FSH secretion

21

Sertoli cells secrete tubular fluid, which does what

provides nutrient support for the spermatozoa

22

The leydig cells synthesize testosterone in response to what

LH

23

As T diffuses into the seminiferous tubules it has a negative feedback on what

GnRH and LH; regulating its own secretion

24

Sertoli cells synthesize inhibit in response to what

FSH

25

Inhibin has negative feedback on what

negative feedback actions in pituitary to regulate FSH

26

Sertoli cells also produce this, which sequesters T needed for spermatogenesis

androgen binding protein (ABP)

27

Sertoli cells convert (aromatize) some testosterone to what

estradiol

28

Testosterone is converted to dihydrotestosterone (DHT) (a very potent non-aromatizable androgen) by what

5α-reductase

29

What is used to convert testosterone to estradiol

aromatase
(also converts androstenedione in the brain and bone)

30

The therapeutic manipulation of testicular hormone enzymes is used to treat what two conditions

cancer therapies
baldness treatment (DHT on hair follicles) 5α-reductase inhibitor

31

Testicular hormones can have what three reproductive effects

sexual differentiation of an XY fetus
development of secondary sex characteristics
expression of sexual behavior

32

What three other effects can testicular hormones have on the body

interact with growth hormone to stimulate skeletal growth
stimulate muscle growth (T is anabolic)
regulate red blood cell synthesis

33

The oocytes in the ovary are arrested in which state

meiosis I; enclosed in a follicle

34

These cells lie outside the follicle, like Leydig cells

theca cells

35

These are the epithelial cells of the follicle

granulosa cells

36

After ovulation, the remaining theca and granulosa cells transform into what

luteal cells of the corpus luteum

37

The ovary secretes which three hormones

E
P
Inhibin

38

What kind of feedback is the cyclical function of the ovary regulated by

positive and negative feedback

39

Theca cells synthesize this in response to LH

androstenedione

40

granulosa cells convert androstenedione to what

estrone then to estradiol

41

estradiol has what affect on the granulosa cell

stimulates granulosa cell function

42

Granulosa cells secrete this, in response to FSH

inhibin

43

When the follicle is developing, estradiol inhibits what

GnRH and LH

44

Inhibin inhibits what secretion

FSH

45

What are the six effects of estradiol

mitogenic (stimulates cell growth)
regulate oocyte development
female secondary sex characteristics
bone deposition
mood
arterial function; vasodilation

46

What are the two stages of the ovarian cycle

follicular and luteal
each lasts 14 days

47

What are the first two stages of the ovarian cycle

gonadotropin rise and follicular development

48

gonadotropin rise and follicular development leads to what

an increase in estradiol (an inhibin) and dominant follicle selstion

49

How is the dominant follicle selected

Whichever one gets the biggest dose of FSH

50

After the follicle is selected then what occurs

estradiol peak
GnRH and LH surge due to positive feedback actions of E

51

After the completion of meiosis 1 and ovulation, this forms

corpus luteum

52

After the corups luteum forms what increases and is inhibited

E and P increases
gonadotropins are inhibited

53

The CL regresses and then what

there is a decrease in steroids
gonadotropin rises, and start over.

54

The menstrual cycle begins when

when the CL regresses and steroid support to the uterine epithelium (endometrium) diminishes

55

This stimulates proliferation of the endometrium

E from developing follicles

56

The follicular phase ends when

with ovulation and formation of the CL

57

Luteal P and E stimulate what four things

uterine secretory activity
increase glandular production of glycogen
increase angiogenesis
decrease in contractility

58

If there is no pregnancy, what occurs

the CL regresses
steroids decrease
and the cycle starts over

59

If there is pregnancy, what occurs

the placenta produces human chorionic gonadotropin (hCG); this is what pregnancy tests detect
it is structurally similar to LH

60

hCG does what

maintains luteal steroidogenesis until the placenta fully develops

61

This is the cessation of the menstrual cycle due to ovarian failure

menopause

62

What two things occur during menopause

loss of ovarial follicles due to atresia of oocytes
reduced steroidogenesis

63

What are the hormonal consequences of menopause

steriods; must rely on adrenal androgens, similar to pre-pubertal condition
there is an increase in gonadotropins due to lack of negative feedback

64

What are the physiological consequences of menopause usually associated with

decreased estrogens

65

This protein direst the indifferent gonad to become a testis

SRY

66

Fetal testis produce what two hormones that regulate differentiation of the internal genitalia

testosterone
mullerian inhibiting substance

67

What does T regulate in the internal genetalia

stimulates the proliferation of the Wolffian duct system

68

True or False
The fetal ovary will produce differentiating factors

False, it does not
lack of T, does not cause Wolffian system to grow
lack of MIS results in proliferation of Mullerian

69

What are the three components of the undifferentiated fetal genetials

genital tubercle
urogenital fold
labiosacral gold

70

These stimulate differentiation of the external genitalia

androgens; mainly T and DHT secreted by the testes
lack of these androgens results in female development

71

What does the genital tubercle develop into in both males and females

glans of penis
glans of clitoris

72

What does the urogenital fold develop into in both males and females

urethra and surrounding penis
labia minor and urethral opening

73

What does the labiosacral fold develop into in both males and females

scrotum and skin of penis
labia majora

74

This is also sexually differentiated due to the effects of T aromatized to E

the brain medial pre-optic area; much larger in males

75

This results from a mutation in the steriodogenic enzymes

congenital adrenal hyperplasia; disruption in normal sexual differentiation

76

In congenital adreanal hyperplasia, the synthesis of cortisol is impaired, which leads to what

decrease in negative feedback resulting in increased stimulation of adrenal cortex and an increase production of adrenal androgens

77

Increased adrenal androgens will have what affect on males/females

it will not disrupt make development, only female

78

Someone with genotype XX with congenital adrenal hyperlasia, will have what symptoms

phenotype is more male
will have ovaries as gonads
but will have wolffian and muellerian ducts
and will have both a penis and vagina

79

What will have if there is 5α-reductase deficiency

development of the penis, scrtum, and prostate is DHT dependent
enzyme deficiency results in failure of differentiation of the external genitalia

80

What completes differentiation involving a 5α-reductase deficiency

increased T secretion with the onset of puberty

81

Someone with a genotype of XY with 5α-reductase deficiency will have what type of symptoms

phenotype is female at birth until puberty
will have testes
will have a penis with Wolffian ducts
will have a normal male appearance after puberty

82

Androgen insensitivity is due to what

a loss of a functional androgen receptor

83

Someone with a genotype of XY will have type of symptoms with androgen insensitivity

phenotype is female
will have testes
no coffin or mullein ducts
will have a short vagina

84

This support luteal steroidogeneis during pregnancy

hCG

85

This stimulated the growth of the myometrium

placental estradiol

86

This reduces uterine contractility and stimulates vasodilation

placental progesterone

87

What are three considerations of the pregnant dental patient

more susceptible to gingivitis and periodontitis due to elevated steroid level
medications and radiographs may affect the fetus
comfort during exam or procedure