ER 12+13+DLA Flashcards
development of the testes?
intermediate mesoderm = leydig and myloid cells
coelomic mesoderm (mesothelium) = sertoli cells
germ cells = yolk sack
testicular transabdominal descent
- retroperitoneal
- through the inguinal canal
- to the scrotum
what forms the tunica vaginalis and how?
processus vaginalis
the evagination of the peritoneal cavity and membrane
three layers of the testis
tunica vaginalis: peritoneum
tunica albuginea: DICT
tunica vasculosa: blood supply
spermatogenesis?
- spermatogonial phase: mitosis
type A dark - reserve stem cells
type A pale - renewing stem cells
type B- mature - spermatocyte phase: meiosis
primary - meiosis I
secondary - meiosis II - spermatid phase
remodeling and maturation
sertoli cells
what do they look like?
what do they do?
what do they secrete
columnar cells with elongated pale nuclei and dark nucleolus
they are supporting cells
form the blood-testis barrier so they do not interact with immune system
secrete inhibin - inhibits FSH secretion
secretes ABP - binds testosterone to keep levels high
secrete MIS
Cryptorchidism?
condition when the testes do not descend into the scrotum
if untreated: sterility increased risk for cancer thickened BM narrow ST only have sertoli cells no spermatogonia
leydig cells
function?
look like?
also known as interstitial cells
large, eosinophilic cells with small round nucleus and lots of fat droplets
function: secrete testosterone
embryo testis development
puberty
hormonal control of the testes by the hypothalamus?
what hormone is released?
GnRH
what does LH and FSH do for the male?
target cells ?
LH targets the leydig cells to secrete testosterone
FSH targets the Sertoli cells to secrete ABP
classical seminoma?
macro and micro signs?
macro:
large, round, polyhedral with distinct membrane
creamy white and homogenous
micro:
sheets of uniform polygonal cells with distinct borders , clear cyto, round nuclei
poorly divided lobules
benign prostatic hyperplasia?
proliferation of the glandular epithelium
(hyperplasia)
affects the transitional zone of the prostate
results in compression of the prostatic urethra
weak urination
difficulty starting and stopping
urge or feeling to urinate
what region do most prostatic carcinomas occur
peripheral zone
adenocarcinoma of prostate?
most common form of cancer in men
usually in males over 50
may spread via lympathatics
will arise in the peripheral zone
micro:
well defined granular pattern
dark cyto
overcrowded
GnRH impact on the gonadotroph (AP)
GnRH binds to the receptor
increases IP3 and DAG
increased PKA and Ca
release of LH/FSH and increase synthesis
effect of LH on the leydig cells?
LH binds to receptor
increases cAMP
increases DNA transcription by PKA
increase the conversion of cholesterol to testosterone
The effect of FSH on the Sertoli cells
FSH binds to receptor
increase cAMP
increase DNA transcription via PKA
releases: inhibin aromatase ABP growth factors
testosterone at target tissues?
converted to dihydrotestosterone
bind to internal receptor
modulate gene expression and increase protein synthesis
actions of testosterone
promotes long bone fusion
increase BMR
increase RBC mass
increase size of reproductive organs
spermatogenesis
secondary sex characteristics
how does testosterone travel in the body?
most is bound to sex-hormone binding globin or albumin
most is in the dihydrotestosterone form
broken down by liver
how is testosterone and inhibin regulated
high levels of testosterone inhibits the hypothalamus and anterior pituitary
high levels of inhibin inhibits the anterior pituitary
mechanism of erection
increase in parasympathetics
decrease in sympathetics
increase in NO and/or ACh which leads to vasodilation
how does viagra, cialis, and levitra work?
these can be used for erectile dysfunction
increasing NO and/or ACh by increasing levels of cGMP by inhibiting it degradation
hypogonadism?
different life stages?
non-functional testes in fetus
lead to development of female sex organs
loss of testes before puberty:
maintain infantile sex organs and characteristics
bones are weaker but longer
might be taller
loss of testes post puberty: decrease in sexual organ size increase in voice pitch loss of bone and protein build-up less aroused
adiposogenital syndrome
inability for the hypothalamus to secrete enough GnRH
het obesity and hypogonadism
affects feeding center
infertility?
sperm count is below 20 million / mL
abnormal shape of sperm
lack of motility
