ER 12+13+DLA

Question 1

development of the testes?

Answer 1

intermediate mesoderm = leydig and myloid cells

coelomic mesoderm (mesothelium) = sertoli cells

germ cells = yolk sack

Question 2

testicular transabdominal descent

Answer 2

1. retroperitoneal
2. through the inguinal canal
3. to the scrotum

Question 3

what forms the tunica vaginalis and how?

Answer 3

processus vaginalis

the evagination of the peritoneal cavity and membrane

Question 4

three layers of the testis

Answer 4

tunica vaginalis: peritoneum

tunica albuginea: DICT

tunica vasculosa: blood supply

Question 5

spermatogenesis?

Answer 5

1. spermatogonial phase: mitosis
   type A dark - reserve stem cells
   type A pale - renewing stem cells
   type B- mature
2. spermatocyte phase: meiosis
   primary - meiosis I
   secondary - meiosis II
3. spermatid phase
   remodeling and maturation

Question 6

sertoli cells
what do they look like?
what do they do?
what do they secrete

Answer 6

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

Question 7

Cryptorchidism?

Answer 7

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

Question 8

leydig cells
function?
look like?

Answer 8

also known as interstitial cells

large, eosinophilic cells with small round nucleus and lots of fat droplets

function: secrete testosterone
embryo testis development
puberty

Question 9

hormonal control of the testes by the hypothalamus?

what hormone is released?

Answer 9

GnRH

Question 10

what does LH and FSH do for the male?

target cells ?

Answer 10

LH targets the leydig cells to secrete testosterone

FSH targets the Sertoli cells to secrete ABP

Question 11

classical seminoma?

macro and micro signs?

Answer 11

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

Question 12

benign prostatic hyperplasia?

Answer 12

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

Question 13

what region do most prostatic carcinomas occur

Answer 13

peripheral zone

Question 14

adenocarcinoma of prostate?

Answer 14

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

Question 15

GnRH impact on the gonadotroph (AP)

Answer 15

GnRH binds to the receptor

increases IP3 and DAG
increased PKA and Ca

release of LH/FSH and increase synthesis

Question 16

effect of LH on the leydig cells?

Answer 16

LH binds to receptor

increases cAMP
increases DNA transcription by PKA

increase the conversion of cholesterol to testosterone

Question 17

The effect of FSH on the Sertoli cells

Answer 17

FSH binds to receptor

increase cAMP
increase DNA transcription via PKA

releases: 
inhibin
aromatase 
ABP
growth factors

Question 18

testosterone at target tissues?

Answer 18

converted to dihydrotestosterone

bind to internal receptor

modulate gene expression and increase protein synthesis

Question 19

actions of testosterone

Answer 19

promotes long bone fusion
increase BMR
increase RBC mass

increase size of reproductive organs
spermatogenesis
secondary sex characteristics

Question 20

how does testosterone travel in the body?

Answer 20

most is bound to sex-hormone binding globin or albumin

most is in the dihydrotestosterone form

broken down by liver

Question 21

how is testosterone and inhibin regulated

Answer 21

high levels of testosterone inhibits the hypothalamus and anterior pituitary

high levels of inhibin inhibits the anterior pituitary

Question 22

mechanism of erection

Answer 22

increase in parasympathetics
decrease in sympathetics

increase in NO and/or ACh which leads to vasodilation

Question 23

how does viagra, cialis, and levitra work?

Answer 23

these can be used for erectile dysfunction

increasing NO and/or ACh by increasing levels of cGMP by inhibiting it degradation

Question 24

hypogonadism?

different life stages?

Answer 24

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

Question 25

adiposogenital syndrome

Answer 25

inability for the hypothalamus to secrete enough GnRH

het obesity and hypogonadism

affects feeding center

Question 26

infertility?

Answer 26

sperm count is below 20 million / mL

abnormal shape of sperm
lack of motility