Endocrine Concepts+ Reproductive Physiology Ucfcom

Front 1

Distinguish between a primary, secondary or tertiary endocrine disorder:

Back 1

A primary disorder affects the target gland itself.

A secondary disorder affects the pituitary gland.

A tertiary disorder affects the secretions of the hypothalamus.

Front 2

Which hormone is the only anterior pituitary hormone that is not secreted in response to hypothalamic hormone?

Back 2

Prolactin, is under negative control by the prolactin inhibitory factor (dopamine)

Front 3

What happens if you cut the infundibulum to all of the hormone secretions?

Back 3

They all lower except Prolactin (since it is under negative control instead of positive control)

Front 4

What does the anterior pituitary secrete?

What does the posterior pituitary secrete?

Back 4

FLAT PEG

ADH (supraoptic nucleus), Oxytocin (para ventricular nucleus)

Front 5

How do catecholamines and thyroid hormones behave?

What are both of these hormone types derived from

Back 5

Catecholamines behave like peptide hormones, thyroid hormones behave like steroids.

Tyrosine

Front 6

What enzyme converts testosterone into dihydrotestosterone?

Back 6

5alphareductase

Front 7

What are the characteristics of testicular feminization?

Back 7

Lack of testosterone receptors means that there is no development of male genitalia.

However, because sertoli cells are still directed to secrete MIS there is also no preferential development of the mullerian duct system (paramesonephric ducts)

If however, the patient only has lack of the enzyme 5alphareductase they are slightly more masculine because tesosterone does have a weak effect.

Front 8

How can congential adrenal hyperplasia affect a fetus?

Back 8

Lack of 21 alpha hydroxylase results in excessive production of adrenal hormones and therefore virilization.

Front 9

What is the first event of true puberty?

Back 9

Increased secretion of FSH and LH during sleep.

Front 10

Function of the testis:

Back 10

Spermatogenesis
testosterone secretion

Front 11

Function of the Epididymis and vas def

Back 11

Site of sperm maturation

Front 12

Function of the Seminal vesicle:

Back 12

Supplies bulk of semen volume
Supplies fructose
Secrete prostaglandins for sperm motility!
Supplies precursors for semen clotting

Front 13

Function of the Bulbourethral glands

Back 13

Secretes mucus for lubrication

Front 14

Function of the prostate

Back 14

Secretes alkaline fluid
Secretes enzymes that trigger clotting
Secretes protease PSA (prostate specific antigen

Front 15

Define infertility:

Back 15

inability to conceive after 12 months of unprotected sexual intercourse

58% related to female factors

Front 16

What makes the Leydig cells secrete testosterone and what does testosterone inhibit?

Back 16

LH = increased secretion of testosterone

testosterone has negative feedback for FSH and LH!

Front 17

What stimulates the Sertoli cells to secrete inhibin and abp?

Back 17

FSH

Front 18

What secretes inhibin and what is its function?

Back 18

Sertoli cells secrete inhibin and they exert negative feedback on FSH!

Front 19

Explain how an erection can occur:

Back 19

2 ways either psychogenic or tactile but the concept is the same.

Erotic stimuli increases the parasympathetic tone, causes release of Nitric oxide which vasodilates, the sinusoidal spaces fill with blood with expands the corpora cavernosa compressing venous outflow.

Spongiosum does not get hard b/c it has to remain patent for the ejaculate to be released

Front 20

How does slidenafil (viagra) work?

Back 20

It inhibits phosphodiesterase type 5, which would normally break down cGMP (the second messenger of the NO pathway)

Front 21

What is the purpose of abp?

Back 21

concentrates tesosterone at the site of spermatogenesis

Front 22

Difference of the negative feedback of Inhibin (spermatogenesis) and tesosterone?

Back 22

Inhibin only inhibits FSH, tesosterone inhibits GnRH from the hypothalamus

Front 23

What is the purpose of the hormone aromatase?

Back 23

Turns testosterone or androstendione into estradiols

Front 24

What is mediated by tesosterone versus dihydrotestosterone?

Back 24

Testosterone-mesonephric duct structures (epid, vas, seminal vesicles); spermatogenesis; negative feedback on ant pit; 2 sexual characteristics; end of pubertal growth; libido

DHT:
Penis, scrotum, prostate; male pattern hair, and baldness;acne;growht of prostate

Front 25

List 10 functions of estrogen:

Back 25

1: development of 2nd sex chars
2: profli of ovarian /granulosa cells
3: maintainence of tubes
4: regulates tissue responsivness
5: negative feedback effects on FSH and LH
6: maintains pregnancy
7: decreases threshhold for uterine contractions
8: increases prolactin but BLOCKS action at the breast
9: decreases LDL cholesterol
10: maintains bone density

Front 26

List 4 functions for progesterone:

Back 26

1: maintains endometrial secretion in the luteal phase
2: negative feedback control of FSH and LH
3: maintainence of pregnancy
4: increases the threshhold for contractions

Front 27

21 alpha hydroxylase deficiency casues-

Back 27

virilization of the fetus, meaning external masculinization-clitoromegaly etc

Front 28

Are FSH/LH levels higher or lower post menopause?

Back 28

Higher, b/c there is no negative feedback-particularly on FSH by inhibins which are usually produced by the ovary.

Front 29

What hormone characterizes the proliferative phase:

Back 29

estrogen

Front 30

What hormone characterizes the secretory phase?

Back 30

progesterone

Front 31

What causes menstruation?

Back 31

lack of progesterone

Front 32

What phase are oocytes arrested in of the cell cycle?

Back 32

meiosis 1

Front 33

Explain hormone fluctuations during the menstrual cycle:

Back 33

Progesterone-spike after ovulation
LH-speak before ovulation
FSH spike at ovulation
estrogen-double spike (combo LH and Progesterone)

Front 34

What initiates the follicular phase of the menstrual cycle:

Back 34

Estrogen and FSH bump

Front 35

What occurs during the follicular phase?

Back 35

Corpus luteum dies= decreased inhibin=increased FSH

Increased FSH causes primary follicles to develop

Granulosa cells secrete estrogen and inhibin under the influence of FSH

Dominant follicle develops that has a high sensitivity to FSH (inhibin is decreasing the level of FSH)

Front 36

Explain the ovulatory phase of the menstrual cycle?

Hint: Ovulhation

Back 36

1: LH surge is caused by the dominant cycle signaling its maturity to the ant pit by increasing estrogen secretion, which exerts positive feedback on the ant pit

2: primary oocyte completes meitoic division to become a secondary oocyte

3: LH, progesterone, and local prostaglandins thin the lining of the ovary so the follicle can pop out

Front 37

Explain the luteal phase of the menstrual cycle?

Back 37

1. the corpus luteum is formed under the influence of LH creating lutein cells

2. cells produce progesterone-prevents another LH surge

3. if pregnancy does not occur the ocrpus luteum degenerates, if implantation does occur the trophoblast cells secrete lh analog HcG which supports the luteum

Front 38

What causes menopause?

Back 38

withdrawal of estrogen because of loss of follicles, FSH and LH surge b/c there is no negative feedback on GnRH

Front 39

Average age of menopause in the USA?

Back 39

51.5

Front 40

How do granulosa cells make estrogen?

Back 40

They use aromatase to turn androgens made from theca cells into estrogen.

Front 41

Why is the first sperm to reach the egg unlikely to fertilize it?

Back 41

The sperm need to undergo capacitation in side the female reproductive track (removes a protein coat)

Front 42

What type of cervical mucous is best for pregnancy?

Back 42

Stretchy, from estrogen (lets em in)

Front 43

Explain the 6 stages of implantation:



BAPMCS

Back 43

1: BINDING: Sperm binds to the zona pellucida via specific binding proteins

2. Acrosome reaction (Cracrosome) cracks the zona pellucida with enzymes

3.Membrane PENETRATION: sperm penetrates zona pellucida to reach the oocyte membrane

4. FUSION-egg and sperm cell membranes fuse

5. CORTICAL RXN-(courts, keeps the other sperm out)- enzymes are released in the egg via exocytosis that hardens the zona pellucida-prevents polyspermy

6-SYNGAMY-male and female pronuclei fuse, chromosomal sex is determined

Birthing Another Person Makes Cervixes Stretch

Front 44

What is capacitation?

Back 44

final maturation event for sperm, occurs in the female reproductive track

Front 45

Four stages of implantation:

Back 45

1. Cuddle-uterine fluid absorption brings the blastocyst closer to the endometrium-pinopods drink up the fluid

2. Hatching-occurs-breakout from the zona pellucida

3. AAI-apposition, adhesion, invasion

4. Decidual reaction-changes in the endometrium to a thicker lining in concentric waves

CHAD was implanted

Front 46

2 functions of the placenta:

Back 46

1. transporting epithelium-nutrient transfer

2. endocrine gland-secretes hormones of pregnancy

Front 47

Why do immuno disorder take a while to be seen in babies?

Back 47

fetal immune system consists of maternal IgG until about 6 months of age.

Front 48

What is the most important peptide made by the placenta?

Back 48

HCG!!!! rescues the corpus luteum =continued progesterone secretion

after 8-9 weeks the placenta takes over progesterone production

Front 49

What is hCS (hPL)? Human placental lactogen

Back 49

hPL-spares glucose, high during pregnancy, reduces maternal insulin responsiveness!!!!

Front 50

What substances does the fetal endocrine system need from the maternal system?

Back 50

LDL cholesterol for steroid synthesis

Front 51

Does the fetus produce progesterone or estrogens?

Back 51

NO! fetus is an androgen sink, it then converts these things to DHEAS to estriol e3 which increases uteroplacental blood flow

Front 52

How does the fetus create estrogens?

Back 52

It uses DHEA-s to DHEA- 16-OH DHEA from the fetal adrenal gland to make e3!!!-increases blood flow

Front 53

The non pregnant uterus is what kind of smooth muscle? The pregnant uterus is what kind of smooth muscle?

Back 53

Non pregnant=multiunit smooth muscle

pregnant=single unit smooth muscle

Front 54

Explain the stages of pregnancy:

Back 54

QASI!! quit acting so infantile!

Plase 0-quiesance-uterus is quiet under *progesterone*. Relaxin is secreted by the corpus luteum and maintains the relaxed state.

Phase 1-(estrogen!!!s)activation-week before parturition there are low frequency myometrial contractions (braxton hicks), and increased oxytocin and prostaglandin receptors as well as new *gap junctions* to promote unified muscle contraction.

Phase 2-stimulation-oxytocin and prostaglandins induce uterine contractions and dilation of the cervix

Phase 3- involution-uterus returns to its normal size with the assistance of sustained contraction, assists in blood clotting (oxytocin)

Front 55

What hormones keep the uterus relaxed?

Back 55

progesterone and relaxin (from the corpus luteum)

Front 56

Timing of labor

Back 56

latent phase-8 hrs

active phase 8-14 hrs slope of cervical dilation happens in this time (to 10 cm) -everything before this is stage 1

Stage 2
delivery occurs from hours 14-16

stage 3 birth until delivery of the placenta

Front 57

What initiates labor?

Back 57

A change in the progesterone/estrogen ratio towards estrogen (decrease in progesterone expression).

Progesterones PGF2alpha causes uterine contraction

Oxytocin maintains labor.

Prostaglandin release and oxytocin to maintain it (Ferguson reflex)

Uterotonin theory (above) means that aspirin can prevent premature labor

Front 58

What are the four shunts of fetal circulation?

Back 58

placenta
ductus venosus
foramen ovale
ductus arteriorsus

Front 59

What systems are still immature at birth of a fetus?

Back 59

GI system
Erythropoesis
immune
liver-jaundice is common as hbf is broken down
renal system-weight loss

Front 60

What are the roles of oxytocin and prolactin in lactation?

Back 60

prolactin is required for milk production

oxytocin stimulates milk ejection

Front 61

What prevents maternal milk production from occuring before childbirth?

Back 61

high estrogen levels and progesterone

delivery of the placenta reduces these hormone and allows lactation to proceed.

Front 62

What regulates prolactin?

Back 62

lack of negative control by dopamine

Front 63

What is the most important stimulus for prolactin secretion?

Back 63

the Suckling reflex which inhibits dopamine release, it also stimulates oxytocin release which causes contraction of myoepithelial cells which cause milk ejection.

Front 64

Why do women not immediately get their period after pregnancy?

Back 64

B/c suckling inhibits the GnRH pulse generator, which supresses FSH and LH

cam result in absence of menses for up to 2 years.

Front 65

Why is it adviseable to breastfeed to prevent vaginal prolapse?

Back 65

Oxytocin release helps stimulate involution so the uterus returns to normal size

Front 66

What hormone is primarily responsible for the development of the breast?

Back 66

brEstrogen

Front 67

When does final differentiation of the breast occur?

Back 67

only in preganncy

Front 68

What is colostrum?

Back 68

Colostrum is secreted initially until milk production gets going, concentrated form of nutrients with a mild laxative effect that helps clear fetal biliruben