Physio Exam 2 Flashcards
Gonadotropin dependent precocious puberty
Blame the Anterior Pituitary
Tx: Long acting GnRH Agonist
(causes desensitization)
Gonadotropin independent precocious puberty
Blame the gonads
Tx: Remove the tumor on the ovaries/testes
LH and FSH
tell the gonads to do their job during puberty
LH and FSH are controlled by
Anterior Pituitary
Hypogonadotropic
problem is in CNS
Hypergonadotropic
problem is with gonads
Kallmans
can’t smell
Tx: Estrogen or Testosterone replacement
Later, can start with GnRH to help Ant Pit work again for fertility
Kallmans
Kall can’t smell
problem with Ant Pit
Turner syndrome
absence of X chromo [XO] No gonads Short stature or delayed/absent puberty Amenorrhea LH and FSH really high bc no negative feedback from Estrogen from gonads
Tx: Estrogen supp and then supplemental sex steroids
Turner syndrome
will never be fertile
Klinefelters
XXY
Failure of normal testicle function (no testosterone release)—> absence of negative feedback to the pituitary
Feminization occurs
Complications: germ cell tumor, breast CA, osteoporosis
Klinefelters
Tx: GH first (Testosterone) and then supplemental steroids
Tx for Turner and Klinefelters
the same
GH first and then supplemental sex steroids
Acrosome reaction
After sperm has passed Zona Radiata, it reaches the Zona Pellucida (gel)
Hydrolytic enzymes are released into Pellucida so that sperm can pass through
Zona Pellucida (gel)
has ZP3 protein that Sperm receptors bind to
Sperm (fertilin) binds to
Integrin receptor on Ovum
A bunch of sperm help to degrade the Pellucida (gel), BUT once the sperm reaches the cell membrane,
only one contributes its genetic material
Zona Reaction
Release of granules containing enzymes to degrade the ZP3 protein so that the Pellucida (gel) layer will harden back up!
prevent multiple sperm from getting to the final step
Zona reaction
granules degrade ZP3
ALSO,
Final maturation of oocyte- signals for completion of 2nd Meiotic division
After Zona reaction
Head of sperm is fully inside of Oocyte
Pronuclei of sperm will eventually fuse with Pronuclei of Oocyte
Binding of Integrin on Ovum to Fertilin on Sperm triggers
Zona reaction
harden gel layer back up and complete 2nd meiotic division of ovum
Estrogen during pregnancy
requires healthy Placenta AND baby
uses baby Adrenal gland to convert Chol –> DHEA Sulfate –> Estriol
Estrogen during pregnancy functions:
Growth of myometrium (muscles for delivery) Develop ductile system of breasts Prolactin release Relax pelvic ligaments Inhibit lactation
Progesterone during pregnancy
Requires only healthy placenta
made from mother cholesterol
Progesterone functions
Makes the uterus a secretory gland
Inhibit premature contractions
Inhibit premature Lactose (baby milk) synthesis
First two trimesters
Progesterone keeps the uterus quiet (aka no contractions)
Levels of High Estrogen as women prepare for parturition (birth)
- Gap jx increase uterus
- Oxytocin receptors increase
- Prostaglandins –> cervical softening
Placenta carries
CRH –> Fetal Ant Pit –> ACTH –> Fetal Adrenal Cortex –> Cortisol and DHEA production
Cortisol
Fetal lungs –> increase pulmonary surfactant –>
DHEA
placenta –> DHEA –> Estrogen
CRH
“placental clock”
Triggers to premature pregnancy
Bacterial infection
Allergic rxn
Multiple fetal pregnancies (twins, triplets)
Role of Nuclear Factor in uterus
NF-B caused by stretching, increased production of Macrophages as a result of increased Pulm Surfactant
NF-B stimulates production of inflammatory cytokines (IL-8) and prostaglandins –> cervical softening
PREMATURE DELIVERY
Prolactin
enzymes for Milk synthesis
Estrogen and Progesterone
helps develop mammary glands but inhibits milk synthesis until baby is born
Prolactin
stimulates secretion of milk
Oxytocin
milk ejection
Removal of steroids at birth
initiate lactation
Estrogen and Progesterone
block the action of Prolactin on the breast DURING pregnancy
Estrogens
Ductal growth
DUCTS
Progesterone
Prolactin
Hcs
Lobules and Alveoli of breast
Prolactin and Hcs
milk enzymes
Anterior pituitary
release Prolactin (leading to more milk production)
Posterior pituitary
release Oxytocin (leading to contraction and milk “let down”)
Stress can affect the Post Pit and inhibit
Oxytocin release
inhibiting “let down”
Prolactin (milk synthesis) release is regulated by
Dopamine (inhibitory)
Thyrotropin-releasing hormone: TRH (stimulatory)
Prolactin
inhibits GnRH
thus inhibiting FSH and LH
No ovarian cycling!!
Irreg menses, very heavy
Dark coarse hair on face, upper arm, abdomen
Persistent acne
Cant get pregnant
High testosterone levels
High LH and FSH
Ovarian enlargement with too MANY follicles, but none dominant (eventually they turn into cysts)
PCOS
PCOS
The follicles turn into cysts
Cysts produce many Androgens
PCOS
“Stein-Leventhal Synd”
Primary product of ovary is Testosterone instead of normal hormones
Testosterone interferes with normal female cycle
46XX
21 hydroxylase deficiency
Virilization
Virilization (masculinization)
Extra levels of Testosterone –> DHT (enlarged clitoris)
46XX
Low glucose and Low cortisol
High ACTH and Testosterone
46XX
21 hydroxylase def
Low cortisol
d/t lack of 21-hydroxylase
cannot be converted into Cortisol, so the precursors instead get made into Testosterone
46XX
21 hydroxylase def
more precursors left over SO
Low Cortisol
High Testosterone
46XX
can be lethal if low levels of Cortisol are not corrected
Optimal Spermatogenesis requires both sufficient levels of
Testosterone
FSH
Spermatogenesis also requires sufficient
Sertoli cells (which are stimulated by both Testosterone and FSH)
Hormone with a pleiotropic effect
meaning several effects
Hormone with a trophic effect
meaning regulates:
- Hormone secretion by ANOTHER gland
- Growth and integrity of that endocrine gland
TRH example of hormone with a Trophic effect
tells pit to stimulate TSH, goes into bloodstream, targets thyroid gland, releases thyroid hormone (secretory) and maintains normal growth of thyroid gland
Endocrine
dumped into plasma to act distally on receptor cell
Paracine effect
hormone regulates processes in NEIGHBORING cells
Autocrine effect
hormone “acts back” , leaves cell but comes back to to regulate process WITHIN CELL OF ORIGIN
acts on those receptors
Intracrine
act on cell of origin but DOESNT EVEN LEAVE CELL at all
Neurocine
hormone that is released from neuron, travels down axon
carried distally either by blood vessel or synaptic transmission
“Classic” endocrine glands
Hypoth Pit Pineal Thyroid and Parathyroid Placenta, ovaries, testes Pancreas GI tract Thymus Adrenal cortex and medulla
“Novel” endocrine glands
Adipose tissue
Heart (epicardial fat)
Skeletal muscle
Chemical structure categories
Peptide (gene is transcribed into mRNA)
Amine (tyrosine)
Steroid (cholesterol)
Peptide (the majority)
water loving
gene mRNA
Amine
derived from tyrosine
Steroid
derived from cholesterol
Majority of hormones are:
Peptide hormones (produced from gene that is transcribed into mRNA)
Peptide hormones
hydrophillic
water loving
gene, mRNA
derived from Amino Acids
Tyrosine is in
Adrenal medulla,
used to make Catecholamines
Tyrosine is the parent A.A. for
Catecholamines and Thyroid hormones
Thyroid hormone is made by
Two tyrosine and Iodine atoms
Catecholamines are made by
modifying the side groups of Tyrosine
Amines
Epi NE Dopamine T4 (Thyroxine) T3 (Triiodothyronine)
Steroids
Aldosterone Cortisol Estradiol Estrogen Testosterone DHEA Vit D
Majority or hormones are
PEPTIDE
Glycoproteins fall under the peptide family
Glycoproteins (type of peptide)
FSH TSH LH hCG have a slight modification: CARB moiety critical in secretion and activity of this hormone
Hydrophillic- water loving- reach target tissue via Cardiovascular system
Peptide hormones and Catecholamines
Hydrophobic
Steroid and Thyroid- need carrier protein
Hydrophillic
dissolved and transported in bloodstream
Concentration of hormone in plasma is determined by:
Production/release of plasma binding proteins
Feedback mechanisms
Glucuronidation
Sulfate conjugation (increases water solubility for excretion)
Peripheral conversion
Internalization of hormone/receptor in peripheral tissue
Group 1 mechanism: Steroid and Thyroid
STD goes right through
steroid and thyroid
Hydrophobic
Dissolve RIGHT THROUGH membrane and bind to nucleus
Group 1 mechanism: Steroid and thyroid
do not have any fancy signal transduction mechanisms bc they can dissolve through and go right to the nucleus
Steroid hormone synthesis
Cholesterol –> Cytosol, ER, mitochondria –> immediately dumped into circulation (no storage)
Amines
Tyrosine –> Enzymatic in cytosol (catecholamines) and Follicular cell and colloid (for thyroid) –> stored in granules or inside the Follicular cells
Follicular cells are found
in the Thyroid gland
Peptide hormone synthesis (the big class)
Specific gene that directs mRNA –> Ribosomes, golgi, ER –> stored in granules until needed
Synthesis of peptide
Gene for hormone transcribed into mRNA (in nucleus) then leaves
Preprohormone –> prohormone (in Endoplasmic Reticulum)
Prohormone –> hormone (in Golgi)
Hormone is stored in secretory vesicles until it is released
Leaving the ER
we have Prohormone
Leaving the Golgi
we have normal Hormone
ER
preprohormone–> prohormone
Peripheral conversion
transfer to something else to increase biological activity
Skin: Vitamin D3
hydroxylation on Liver and Kidney–> 1,25 Dihydroxyviamin D3
Testes: testosterone
Androgens formed
conversiont ot E2 in brain and testes
DHT and E2 final products
Thyroid: Thyroxine T4
Conversion in most tissues to make T3 (final product) Triiodothyronine
T3
active form
Humoral release
activated by blood borne substrate
Humoral release
the concentration of substrate is above or below “setpoint”
i.e. Ca levels low, trigger PTH release from Parathyroid gland
Neural release
Psychological stress Emotion Fight or flight Exercise Hypoglycemia Shock Hemorrhage Heart dz CNS is secreting the hormones
Examples of Humoral release
Calcium and PTH
Glucose and Insulin
Neural release
Adrenal gland releases hormones (Epi and NE)
Hormonal release
Classic endocrine gland
Network of hormonal connection starting at Hypoth
Hormonal release
Hormones regulate the secretion of OTHER hormones
Long example of Hormonal release
TRH stimulate pituitary secretion of TSH which stimulates endocrine gland (thyroid) to release thyroid hormone (T3/T4)
What types of hormones have to bind to receptor on the cell surface?
Peptides and catecholamines (hydrophobic, cant get through)
What types of hormones diffuse through and go straight to nucleus?
Steroid and Thyroid hormones
Decrease in max response
Decrease in target cells
Decrease signal transduction mechanisms
Decrease in sensitivity (max response can still be reached)
More hormone needed in order to get max response
Decrease in affinity
Decrease in receptor #
Example of decrease in sensitivity
Insulin and obesity
Permissiveness
Hormone cannot exert its effect unless it has help from another (needing a bathroom buddy in order to be able to pee)
Autologous up/down regulation
hormone regulates its own receptor affinity/number
Heterologous up/down regulation
hormone regulates number/affinity of ANOTHER hormone’s receptor
Anterior pituitary
Metabolism Growth Reproduction Lactation Response to stress
Posterior pituitary
Water balance Birth and lactation (lactation is in both) Regulate BP Cardiac fx Diuresis
Main products of posterior pituitary
Oxytocin
AVP/ADH
Main products of Anterior Pituitary
ACTH Growth hormone TSH Prolactin FSH
Post pit
Magnocellular neurons –> downt Infundibular process –> end in Post pit –> hormones into capillary bed
Ant Pit
Parvicellular neurons –> median eminence with releasing hormones–> hypothalamo-hypophyseal portal vessels –> Ant Pit –> regulate secretion of Tropic hormones
Ant pit
either inhibiting or releasing hormones
Vascular link from hypothalamus and Ant PIt
Parvicellular
Ant Pit
Secrete hormones that are either inhibitory or stimulatory
GHRH
Growth hormone releasing hormone
Act on somatotrophs, which release Growth Hormone
TRH
stimulating hormone
Thyrotropin releasing hormone
acts on Thyrotrophs
Target thyroid gland
T3 and T3
Also maintains growth (trophic effect)
Somatostatin
INHIBITORY
causes decrease in GH and TSH
TRH
also involved in Prolactin glands- mammary glands- breast development and milk synth
GnRH
stimulates production of LH and FSH (in gonads)
LH
Synth of Estrogen
Secretion of Testosterone form Leydig cells
FSH
Development of follicle
Initiate spermatogenesis
CRH
acts on Corticotrophs, makes ACTH which then acts on Adrenal glands
Trophic Result: growth of Adrenal gland, synth of Corticosteroids
PRF
Prolactin releasing factor
mammary glands
breast develop and milk synth
Dopamine
INHIBITORY
inhibits prolactin release (inhibits milk synth and breast development)
Hormones of post pit
ADH and Oxytocin
Oxytocin and ADH are made by two types of neurons in the Hypoth
Supraoptic
Paraventricular
ADH and Oxytocin
Peptide hormones
Oxytocin
binds NP1
ADH
binds NPII
Central Diabetes Insipidus
absence of NeurophysinII can lead to no ADH being released into blood
Neurophysins
keep the hormone in the axon for as long as it needs to be, then allows it to be released
messed up Neurophysins or deficiency
leads to low levels of the hormone
ADH example
Diabetes Insipidus
ADH
VERY sensitive to changes in Plasma Osmolarity
anything above 280-284
Homeostatic adjustments for dehydration
Re-establish plasma osmolarity
ADH secretion
Water reabsorp
Decrease urine output
Stimulate thirst
ADH is less sensitive to volume depletion
than osmolarity
Changes in blood volume (specifically loss here)
Baroreceptors
also activates ADH secretion if BP is too low
Distention of cervix and Uterine contraction
Stimulates Oxytocin release
Oxytocin is also important cardiovascular and cardiometabolic
cardio renal axis
Regulating BP
Oxytocin
produced in heart
receptors in heart
Part of Oxytoxin- natriuretic peptide NO axis
OT in heart
stimulates ANP/BNP release from cardiomyocytes and then ANP stimulates release of NO from vascular endothelium
Protective
Nucleus Tractus Solitarius NTS
is in the Medulla Oblongata
What activates the Cardio-Renal axis? baroreceptors?
HTN and
Hypervolemia
Oxytocin is cardioprotective because
decreases work of heart by decreasing BOTH Chronotropy and Ionotropy
Opening up blood vessels
opening up flood gates of Kidney to allow diuresis
Local oxytocin system in the heart
OT receptors
Locally produced oxytocin
Pituitary produced oxytocin
Either one causes same effect: NO release
Bradycardia
Negative ionotropy
Increased glucose uptake
Oxytocin effect in heart
like insulin!!! but different mechanism.
increased in glucose uptake BY THE HEART!
Sertoli cells secrete:
Anti-mullerian hormone
Androgen binding protein
Inhibin
Leydig cells secrete:
Testosterone
Where are germ cells and Sertoli cells?
Seminif tubule
Where are leydig cells?
connective tissue
Two essential products of testes
Sperm
Testosterone
Spermiogenesis occurs in the walls of:
Seminif tubules
Spermatogonia (diploids) become
Spermatozoa sperm (haploid)
After 2 rounds of Mitosis in males
Create 4 diploid spermatocytes
Double strand DNA
After 2 rounds of MEIOSIS in males
Now have 16 haploid spermatocytes/spermatids
Single strand DNA
Tight jxb /w Sertoli cells
Blood-testes barrier
Prevents immune cells from accessing spermatozoa, REQUIRED for fertility
Early sperm cells have more communication with outside world, but once they pass the Blood-Testes barrier,
Now entirely dependent on the Seminiferous Tubules for nutrients
an EXLUSIVE area inside the seminif tubules
Gap jx
allow for nutrients to be exchanged b/w sertoli cells
tight jx
hold young sperm in place together, not ready to be released yet
Cytoplasmic bridge
allows genetic info txr from X–> Y
What two hormones stimulate Sertoli cells?
Testosterone
FSH
From “cell like” Spermatids –> “animal like” Spermatozoa
SpermIOgenesis
Spermiation
“Release!”
release sperm from sertoli cells syncytium into the Seminif tubules
Spermiation
pass thru Rete testes
Where are sperm stored and further matured?
Epididymis “maturation area”
SpermATOgenesis
germ cells –> spermatozoa
SpermIOgenesis
packaging “cell like” spermatids –> “animal like” spermatozoa
SpermIATION
release from Sertoli cells tight jx
Kiss1 neuron in ARC nucleus in MALES
always stimulate GnRH
Kiss1neuron in ARC nucleus in FEMALES
can be inhibitory or stimulatory
FSH
Tells Sertoli cells to secrete Inhibin and Androgen binding protein
LH
tells Leydig cells to produce Testosterone
Inhibin regulates
FSH
Testosterone regulates
LH and FSH by negative feedback
What enzyme is vital for any steroid hormone?
Cholesterol desmolase- rate limiting
What stimulates Cholesterol desmolase to do its thing?
LH
T –> DHT via
5-a-reductase
T–> E2 via
Aromatase
DHT effects
external
Diff of penis, scrotum, and prostate
Hair/baldness
Prostate
Sebaceous
Testosterone effects
Diff of Epididymis, vas deferens, and Seminal vesicles
Deep voice
Neg fdbk on Ant pit
Libido (sex drive)
Rate of sperm production is set by
Retinoic acid signaling within the Sertoli cells
timing controlled by Vit A
When do Sertoli cells cease proliferation?
End of puberty
What determines the spermatogenic potential of the testes?
of sertoli cells
Average sperm count
20-40 million per ml/ejacu
Oligospermia (little)
<15 million
Taking too much Testosterone (Aka steroids) messes with sperm production bc
You are causing Testosterone to have a negative feedback on FSH (which would usually tell Sertoli cells to do their thing AKA make sperm)
synergistic effect on spermiation? (Release of sperm)
FSH and Testosterone
DHEA
An androgen produced from Adrenal glands
DHT
Male pattern baldness
ppl with deficiency of 5-a-reductase
DONT GO BALD
bc they cant convert T–> DHT
5-a-reductase activity
leads to baldness
Beard growth
DHT and IGF-1
Who does NOT go bald?
Androgen-insensitivity
Castrated
5-a-reductase deficient
DHT and TGF-B1
Lead to thinning of hair!!
Propecia (finasteride)
block 5-a-reductase Non-competitive blocker (does not let go) blocks T --> DHT Treats: Enlarged prostate Baldness
Propecia (finasteride)
Baldness
Enlarged prostate
Propecia (finasteride)
Erectile dysfx
Loss libido
Reduced ejaculate
Propecia (finasteride) DO NOT GIVE TO PREGNANT WOMEN
dangerous bc blocking DHT in utero can have profound effects on MALE BABY DEVELOPMENT
What organ makes up most of the ejaculate? (60%)
Seminal vesicles
- Fructose
- Prostaglandins
- Clotting factors
Prostate produces 20% of ejaculate
Secretes
-Alkaline fluid to counteract acidic vagina
Bubourethral glands produce 10% of ejaculate
Lubrication
Seminal vesicles
Fructose
Prostaglandins
Clotting factor
Prostate
Alkaline fluid (for pH)
Bulbourethral glands
Lubrication
3 main dz of prostate
- BPH
- Prostatitis- infection
- CA of prostate
How many corpus cavernosa do males have?
Two
How many corpus spongiosum do males have?
One
Integration site in CNS of erectoin
MPOA- medial preoptic area
Order of information in erection
Amygdala info –> MPOA integration –> Paraventricular nuclei of hypoth –> grey matter S2-S4
Erection achieved by (3 possibilities)
Higher brain activity (thinking)
Mechanical stimulation of glans provides sensory fdback to S2-S4
Periodic parasymp impulses from sacral erection generation center
NO
activates guanyl cyclase
increases cGMP
LOWERS ca release
vasodilation
Increase of flow into cavernosa and prevent blood flow out
Increase BF to cavernosa thanks to cGMP
AND
contraction of muscles around base of penis to keep blood from getting out
Flaccid state
BF into penis is limited d/t contraction of Helicine arteries and Trabecular sm.muscle
Erection state
Relaxation of Helicine arteries
Compression of what reduces venous outflow during erection?
Subtunical venules
Pathway of sperm ejaculation
Vas deferens –> Ampulla –> Urethra
Role of the Internal urethral muscle/sphincter
Prevents retrograde sperm ejaculation into the bladder
What degrades cGMP?
Phosphodiesterase
PDE5
Phosphodiesterase inhibitor can treat Erectile Dysfx
PDE5
Viagra/Sildenafil
Cialis/Tadalafil
Levitra/Vardenafil
Maintain high levels of cGMP
Vasectomy
ligation of vas deferens
accessory gland functions are unnaffected
semen (BUT NO SPERM) are still produced
T not affected
Vasectomy
Sperm can no longer move thru the ejaculatory duct- are degraded by phagocytosis
Vasecotomy, what will semen have in it?
everything normal but NO SPERM (sperm was degraded by phagocytes bc it could not get through the ejac duct)
LH stimulates Thecal cells to convert Cholesterol ——chol.desmolase—-> Androgens
Androgens then diffuse over to Granulose cells where FSH stimulates the conversion of Androgens ——-aromatase—–>Estradiol
FSH
less frequent pulse from GnRH hypoth
LH
more frequent pulse from GnRH hypoth
As follicular phase proceeds, the levels of Estrogen in amtrum are building up
eventually causes a switch from negative feedback (-) to positive feedback (+) on the anterior pituitar
Buildup of Estrogen during follicular phase and switch to positive feedback (+) leads to
More GnRH released –> more FH and LSH released as a result, BUT Inhibin is keeping FSH in check so we just have a LH SURGE
Thx to LH surge
Primary --> Secondary oocyte Meiosis resumed Enzymes help follicle get thru 2 layers Increase prostaglandins Remainder parts turn into Corpus Luteum
What restores the normalcy of feedback after LH surge?
Progesterone has a negative feedback on hypoth and pit which suppresses the (+) of Estrogen, SUPPRESSING A 2nd LH SURGE!
Suppression of 2nd LH surge
Progesterone
If any changes in woman cycle occurs, which stage is it?
First half
Follicular phase which corresponds to Uterine Proliferative phase
After day 14
Physiologically, the Luteal and Progestational/Secretory phases are pretty consistent.
Rise in Estrogen means
Rise in RECEPTORS for Progesterone. Estrogen does a great job at prepping the body for Progesterone.
Progesterone
“hormone of Pregnancy”
Progesterone acts on Estrogen primed tissue and
antagonizes Estrogen’s effects
Prostaglandins are responsible for
Contraction of Uterus during Menses
Cramps
GI discomfort
PMDD
Premenstrual Dysphoric Disorder
(bloating, wt gain, breast tend, mood swing, depression, unable to work effectively)
5% of women
Meds
No TDF
Ovaries develop
Testes produce
Testosterone —> DHT and Wolffian
DHT
External male genitalia
Wolffian ducts
Male internal reproductive tract
Absence of testoterone
female External genitalie
Absence of Mull-Inh factor
Female internal reproductive tract
What secretes Anti- Mull hormone?
Seroli cells
5-a-reductase deficiency
all of a sudden male develops at Puberty
male internally all along, but not enough DHT–> testosterone conversion to make Male external until puberty
Hormones important for “growth spurt”
IGF-1 and GH
Gonadotropin dependent
Meaning depending on the gonadotropins- problem with CNS
increased gonadotropins (LH and FSH)
Gonadotropin independent
Blame the gonads
Increased gonadal hormones
Kallmans
Can’t smell
CNS problem
Hypo Hypo
Klinefelter and Turner
Hyper hypo
Blame the gonads
Kallman
Can’t smell
Tx for Kallman
Supp sex steroids (FIRST, this is unique) Estrogen or Progesterone
later GnRH
Tx for Klinefelter and Turner
GH first,
then Supp sex steroids
Once sperm reaches the alkaline pH of the cervix (alkaline thx to Estrogen) it is activated by
Cholesterol withdraw
Surface protein redistribution
Ca influx (motility)
What triggers Acrosomal reaction?
Receptors on the sperm bind to ZP3 protein in the Zona Pellucida
Acrosomal rxn
breakage of this cap so that the enzymes can be release and break down the egg wall
Acrosomal rxn
an “army” of sperm help break down, but only one gets through to actually fertilize the egg
Zona rxn
the re-hardening of zona pellucida, making sure only 1 sperm fertilizes the egg
Zona rxn
degrade ZP3
completion of final maturation of Oocyte!
Ovulation
day 14
Optimal implanatoin
day 20-24
hCG
rescues Corpus luteum and maintains until Placenta takes over
In order for the placenta to make Estrogen, requires
BOTH fetus and placenta
Needs fetus Adrenal glands (DHEA) and fetal Liver
What does the placenta need in order to make Progesterone?
only placenta
Fetal Adrenal gland
DHEA
CRH “placental clock”
CRH leads to production of
ACTH which tells Adrenal cortex to produce: Cortisol –> pulm surfactant, and DHEA –> Estrogen