low total testosterone
high LH and FSH
semen volume and [ ] low
explain high FSH LH
because feedback from low testosterone
47 XXY
klinefelters
most common Sx klinefelters
infertility and gynecomastia
most common genetic form of male hypogonadism
klinefelters
sex determining region on Y chromosome
SRYtranscription factor (testis determining factor
what hormone prevents the mullerian ducts from progressing
AMH
anti-mullerian hormone
what is required for development of seminal vesicles, ejaculatory duct and vas deferens
testosterone
what cells produce tesosterone
leydig cells
which hormone stimulates fetal leydig cell production of testosterone during development prior to fetal pituitary LH
hCG
required for development penis scrotum and prostate
DHT
dhydrotestosterone
which has highger affinity for Testosterone R
DHT
what enzyme is required for conversion testosterone- DHT
5 alpha reductase 2
what produces AMH
sertoli cells
what promotes development of gynecomastia
presence of E
increased E:T ratio
peripheral conversion T to E via CYP 19 aromatase
what hormone normally initiates puberty
pulsatile GnRH
what are gonadotropin levels in primary hypogonadism
elevated
androgen decreased
major actions of andorgens
wolffian structures erythropoietin synthesis bone growth libido etc..
which form is most circulating T found
SHBG
serum albumin
least amount is free
what protein maintains T [ ] in testes
ABP androgen binding protein
why is it important for T to be concentrated in testes
needs to be at least 100x circulating levels to promote spermatogenesis
What promotes secretion of LH and LSH
low hormone levels ( E and T)
pulsatile GnRH
FSH works on what cells
sertoli
LH works on what cells
leydig
Why would continuous GnRH be a Tx for prostate CA
constant GnRH dec LH and FSH
so dec T
key functions of sertoli cells
produce aromatase maintain blood testis barrier R for hormones produce ABP produce AMH
3 key hormones promote adequate spermatogenesis in normal male
high T
FSH
LH
GH affects spermatogenesis how
early division of sperm
what Tx could you use for klinefelter Syndrome
androgen replacement therapy
likely effect of giving exogenous T to klinefelter male
virilization of secondary male sexual traits
can exogenous T of klinefelters male promote fertility?
no
seminiferous tubule likely is destroyed
failure of testes to descend impairs what aspect of repro function
maturation of spermatogonia because of temperature differene
dec in facial and axillary hair and dec penile length and hypogonadism
deficiency in what androgen explains findings
DHT
generate Ab that bind and neutralize FSH bioactivity
expected to have a feedback decrease in what
decreased serum inhibin B levels
sertoli cells normally do what in seminiferous tubules
maintain blood testis barrier