Path 1 - Female Repro 1

drraythe's version from 2016-05-03 10:52

Reproductive Embryo (Know everything, the Doctor lies! Dr. Newton's questions are extremely hard & he doesn't give back points!)

Question Answer
What are the 2 components of the urogenital ridge?Mesonephric & Genital ridges
The Mesonephric ridge turns into?Wolffian (Mesonephric) tubules/ducts
Mullerian (Paramesonephric) ducts
The Genital ridge turns into?Undifferentiated stem cells migrate to the Genital ridge from the yolk sac → the genital ridge develops into an Undifferentiated Gonad (Cortex = Ovary, Medulla = Testies)
Which parts of the undifferentiated gonad become the ovary or the testes?Ovary = Cortex (O & C look similar)
Testicle = Medulla (boys go deep inside)
**MALE - Wolffian tubules & ducts become?Epididymis
Ductus Deferens
Seminal Vesicles
**MALE - Urogenital sinus becomes?Prostate & Bulbourethral Glands (a sinus is a place for gland secretions to go into)
MALE - Genital tubercle becomes?Penis
MALE - Genital folds become?Prepuce
MALE - Genital swellings become?Scrotum
**Wolffian duct (Mesenephric) is for _,
Mullerian duct (Paramesonephric) is for _?
Wolf = Boys
Mule = Girls
(that boy is a wolf in sheep’s clothing, girls carry the baby (mules carry things))
**FEMALE - Mullerian ducts become?Oviducts
Anterior Vagina
**FEMALE - Urogenital sinus becomes?Caudal Vagina
FEMALE - Genital tubercle becomes?Clitoris
FEMALE - Genital folds & Genital swellings become?Vulva

Sexual Differentiation

Question Answer
Which gender differentiates 1st?MALE (boys are “done” quick)
Steroidogenicfactor 1 (SF-1) controls?Part of sexual differentiation
What’s the SRY protein (SRYp)?Coded by Y-chromosome
Testes-Determining Factor that induces undifferentiated gonad to develop into testes
What 3 factors play a role in sexual differentiation in the MALEY chromosome
Expression of SF-1
Which transcription factor is MOST important in differentiation/maintenance of Sertoli cells?Sox9 ( Sertoli, Sox)
What does sox9 do?Differentiation/maintenance of Sertoli cells (male) ( Sox Sertoli)
After testes formation, what 2 cells develop & what 2 hormonal products do they secrete?(1) SERTOLI CELLS will secrete MULLERIAN INHIBITORY SUBSTANCE (MIS) (AMH (Anti-Mullerian Hormone) / MIF(Mullerian Inhibitory Factor) )
Sertoli cells make?Mullerian Inhibitory Substanance (MIS/MIH/AMH)
Interstitial/Leydig cells make?Testosterone
What does MIS/AMH/MIF do for fetal repro development?Czs regression of the Mullerian ducts (female stuff)
What does Testosterone do for fetal repro development?Promotes development of Wolffian ducts (male stuff) (Testosterone = Epididymis, Ductus Deferens, Seminal Vesicle, & Ampulla)
What induces development of Penis, Scrotum & Prostate?Dihydrotestosterone (DHT) (NOT just Testosterone! JUST Testosterone stimulates the Wolffian ducts which becomes Epididymis, Ductus Deferens, Seminal Vesicle, Ampulla)
Explain how Dihydrotestosterone (DHT) is made, & what it doesTestosterone is converted into DHT by the enzyme 5-alpha reductase. DHT induces development of Penis, Scrotum & Prostate (stuff guys Double care about)
DAX-1 does what?(FEMALE) Important in ovarian development & repression of testicular development (Dax's last host was female)
Paramesonephric aka? Mesonephric aka?Para = Mullerian (female) (girls carry the baby)
Mesonephric = Wolffian (male) (that boy is a Wolf in sheep's clothing)

Disorders of Sexual Development (DSD)

Question Answer
Usually you can't tell what went wrong when there is a Hermaphrodite (intersex) animal. How do they usually present?Poorly differentiated external genitalia w/ part or all of the internal genital organs of both sexes (when you go into your spay & pull out 1 ovary &1 testicle. Things that make you go 'hmmmm')
What constitutes a "true" Hermaphrodite (intersex)?They have ovatestes (which means they possess gonadal tissue of BOTH sexes)
What constitutes a "Pseudo-Hermaphrodite"?They only have the gonadal tissue of 1 of the sexes (Male Pseudo-Hermaphrodite has male tissue, for instance) still has ambiguous genitalia
***Intersex calf: FREEMARTIN → what czs freemartins to occur?A female calf is born co-twin w/ a male calf
In utero stem cells from male & female calf mix via Large Bore Anastomoses in the placenta
Both calves are XX/XY Chimeras bc of the cells they shared
Some Sertoli cells are produced in the female ovary → MIS/AMH/MIF is produced in varying amounts in female calf
Her Mullerian ducts will be inhibited to varying degrees → Oviducts/Uterus/Cervix/Anterior Vagina do not develop properly
There may also be some development of Wolffian duct structures in female (rudimentary Seminal Vesicles)
How will a freemartin present?Variable development of tubular genitalia & no communication of cranial & caudal portions of the Vagina (Vagina usually ends blindly)
External genitalia will be normal to hypoplastic, there might be some clitoral enlargement
Male twin is usually minimally affected
Which 2 species/breeds of those species are most likely to have XX sex reversal?(1) Dogs, esp. cockers (XX w/ a cock)
(2) Goats, esp. Saanan/Toggenburg (Polled Intersex Syndrome [PIS])
(XX Cocker w/ enlarged Clitoris)
What's happening in XX sex reversal?Gonadal (Phenotype) sex does NOT follow chromosomal sex. There can be XX true Hermaphrodites (has both types of gonadal tissue - Ovatestes) or XX males (Male-Pseudohermaphrodites )
What is happening w/ XX sex reversal in cockers? What are the 2 kinds?The exact pathogenesis unknown, but it is an autosomal trait where the Sex Determining Region is missing in affected females (XX) & it is thought that there is activation of testes differentiation w/o the SRY gene in this case is due to a Mutant Autosomal Gene (sox9 or something)
XY individuals (males) will be normal
2 kinds of presentations of XX individuals:
XX True Hermaphrodites or
XX males (Male Pseudo-Hermaphrodite)
XX Sex Reversal: How do the XX true Hermaphrodites present? How common is this?90% of cases present this way (true hermies)
They will present as Partially Masculinized Females (enlarged clitoris, etc) w/ ovatestes
XX Sex Reversal: How do the XX Male Pseudo-Hermaphrodites present? How common is this form?10% of the cases present like this. In this case, there is testicular tissue, leading to malformed male external genitalia & cryptorchid aspermatogenic testes
XX Sex Reversal: (for clarification) Which breeds of GOATS get Polled Intersex Syndrome (PIS)? Condition its related with? How does this happen?Saanan & Toggenburg goats
Associated w/ Hornlessness (being ‘Polled’)
If they are Heterozygous for the hornless gene, they are hornless & normal
If they are Homozygous for the hornless gene they will have varying degrees of sex reversal → Could be XX males who are just sterile, Hermaphrodites w/ a female phenotype, or XY males that are infertile
The condition is czd by a gene deletion on chromosome 1 of the goat & is linked w/ the poll gene, which czs reduced inhibition of testicular development w/ Sertoli cell differentiation, leading to production of SOX9 & Anti-Mullerian Hormone (AMH) & variable inhibition of the Mullerian duct system & Wolffian duct system
Androgen Insensitivity: AKA? Affects what spp? What happens here & what is the resulting animal like?AKA: Testicular Feminization in HORSES
This condition results in an Equine Male Pseudo-Hermaphrodite (XY genotype w/ undifferentiated testes)
There is an XY genotype & SRY is produced → undifferentiated gonad becomes a testes → Sertoli cells make MIS → Mullerian ducts regress → Interstitial cells in the testicle produce Testosterone***BUT*** there is either a lack of enzyme to convert T to DHT or there IS production of DHT, but there is a lack of a receptor for DHTWolffian ducts ALSO regressexternal genitalia that appear female, but the horse is XY w/ some male tissue inside
Persistent Mullerian Duct Syndrome: Who does this happen in most? What is the genotype & phenotype of affected animals?Miniature Schnauzers!!! (Basset hounds in the UK)
XY genotype, Approx 50% have intra-abdominal testes (1 or both) & remaining 50% scrotal testes
Affected dogs will have male external genitalia (except cryptorchid) & Oviducts, Uterus, Cervix & Anterior Vagina (Mini-Schnauzers persistently love to be around mules)
What is happening in Persistent Mullerian Duct Syndrome?XY dog gets as far as the undifferentiated gonad becoming a testicle & may even produce MIS BUT there are no fxnal MIS II receptor cells on the Mullerian duct cells to detect the MIS → Mullerian ducts continue to develop → XY dogs will have male external genitalia (except cryptorchid) as WELL as Oviducts, Cervix, & Anterior Va-J-J (Mullerian ducts were NOT inhibited by MIS) (persistent lack of receptors leads to persistent female junk in a male dog)