Male Repro Flashcards
consists of
spermatic cords
seminal vesicles
ductal deferens
ejaculatory ducts
prostate gland
bulbourethral glands
epipydymides
2 testes
what is the scrotum
pouch of pigmented skin, fibrous, connective tissue and smooth muscle
divided into two compartments each holding one testicle, one epdidymis and one end of the testicular spermatic cord
where does it lie
below the pubis symphysis
infront of the upper part of the thigh and behind the penis
what is the testes
male repro organ
suspended by the scrotum by the spermatic cord
what are the three layers of tissue in the scrotum
tunica vaginalis
tunica albuginea
tunica vasculosa
tunica vaginalis
double layer membrane which forms the testes outer covering
down growth of the abdominal and pelvic peritoneum
in foetal development the testes begins at the lumbar region in the abdominal cavity which then descends into the scrotum, taking the peritoneum, blood vessels, lymph vessels and different duct with them
it eventually becomes detached from the abdominal peritoneum
tunica albuginea
fibrous covering, middle layer extends inwards forming septa
divides the glandular structure into lobules (200-300)
tunica vasculosa
inner layer of capillaries supported by connective tissue
dartos muscle
found in the scrotum dermis, contraction causes the scrotum skin to wrinkle, raising the scrotum
cremaster muscle
layer of skeletal muscle, which moves the testes away or towards the body to maintain optimum temperature of spermogeneis - cremaster reflex
seminiferous tubule
1-4 lobules of germinal epithelial cells, composed of spermatogonia and sterols cells, cells of leydig surround the tubules (secrete testosterone). At the upper pole of the testis, the tubules combine to form a single tubule, thus us repeatedly folding and tightly packed forming the epididymis
what does the epididymis leave the scrotum as
deferent duct in the spermatic cord
what pass to the testes via the spermatic cord
blood and lymph vessels
spermatic cord
suspends the testes in the scrotum
each cord: testicular artery. testicular vein, lymphatics, deferent duct and testicular nerves
covered by a sheath of smooth muscle, connective and fibrous tissue which extends through the inguinal canal and it attached to the testes at the posterior wall
what could happen if there is a left testicular tumour
cause an expansion in the left testicular even which can impact the left kidney due to drainage issues
arterial supply
testicular artery branches from AA just below the renal artery
venous drainage
testicular vein -> abdominal cavity
left vein opens into the left renal vein
right vein opens into the IVC
lymphatics
LN around the aorta
nerve supply
branches from T10/T11 nerves
functions of male repro
production, maturation and storage of spermatozoa
delivery of spermatozoa in semen into the female urinary tract
<0.5Gy effect on the testes
oligiospermia (low sperm count)
can occur 1-4 years after radiation
0.5-2Gy effect on testes
azopsermia (complete loss of sperm count) can return to normal after around 3.5 years
shouldn’t try for a baby for at least 18 months as risk of genetic damage
> 2.5Gy
sterility
what is the indirect damage to the testes
RT to the brain (pituitary gland)
are cells of leydig radioresistant or radiosensitive
radioresistant
deferent duct
passes up from the tests through the inguinal canal and ascends medially towards the post wall of the bladder, at the end of the lower region each SV opens into a short duct which joins the deferent duct to form the ejaculatory duct
SV
two small fibromusclar pouches lined with columnar epithelium, lying post bladder
contract and expel seminal fluid in ejaculation
seminal fluid forms 60% of the volume of semen, is alkaline to protect the sperm in the acidic environment of the vagina
contains fructose for fuel
ejaculatory ducts
two tubes, each formed by the union of the duct from a SV and deferent duct
pass through the prostate gland, joining the urethra carrying seminal fluid and sperm to the urethra
composed of the same layers as SV
prostate gland
lies infront of the rectum and behind the pubis symphysis
completely surrounded by the urethra as it emerges from the bladder
outer fibrous covering, enclosing glandular tissue wrapped in smooth muscle
secretes a thin milky fluid which makes up 30% of fluid in the semen
contains a clotting enzyme which thickens the semen in the vagina, increasing the likelihood of it being retained close to the cervix
two functions of the testes
production of testosterone
spermatogenesis
production of testosterone
stimulates testicular descent prior birth
regulates spermatogenesis
maintains males accessory organs
maintains and develops secondary sex characteristics
stimulates sexual behaviours and drive
spermatogenesis
directly stimulated by testosterone
indirectly stimulated by FSH
begins in the spermatogonia (SC) in the outer layer of the seminiferous tubules
in the mucosa one daughter cell remains undifferentiated at the basement membrane whilst the other (primary spermatocyte) is pushes towards the lumen of the seminiferous tubule
in meiosis I, DNA replication occurs, chromosomes seek their match and join forming a single chromosome with two copies of DNA, At the end of the division the two secondary spermatocytes will have 23 chromosomes but 2 DNA copies
in meiosis II chromosomes split forming 4 daughter cells = spermatids each with 23 chromosomes
spermatids mature to become spermatozoa this occurs in the cytoplasm of the Sertoli cells
spermiation
detachment of sperm from the Sertoli cells, which release into the lumen of seminiferous tubules
three parts of the urethra
prostatic
membranous
penile
prostatic urethra
originates from the urethral orifice of the bladder and passes through the prostate gland
membranous urethra
shortest and narrowest part of the urethra, extends from the prostate gland to the bulb, passes through the penile membrane
penile urethra
lies within the corpus spongiosum and terminates at the external urethral orifice in the glans
internal sphincter
a ring of smooth muscle at the neck of the bladder, prostate gland sits below this
external sphincter
ring of skeletal muscle surrounding the membranous part
what is ejaculation
sperm is expelled from the epididymus and passes through the deferent duct, ejaculatory duct and the urethra. contractions of the smooth muscle (deferent duct) propels semen
contractions are under sympathetic stimulation
SV walls and prostate gland also contract adding their contents to the fluid passing though the genitile ducts
causes semene to travel out of the external urethral orifice sphincter
what ph is semen
slightly alkaline to neutralise the acidic environment within the vagina
what happens if the sperm isn’t ejaculated
sperm dies and reabsorbed by the epididymis
lymphatics of the skin and prepuce
superficial inguinal
presentation: fumigating inguinal node, broken through the skin surface
gland and corpora lymphatics
deep inguinal node into external iliac
three sections of the penis
root, shaft and glans
root
anchors the penis to the perineum
shaft
externally visible part, which is movable
formed of three cylindrical masses of erectile tissue and smooth muscle
erectile tissue is supported by fibrous tissue covered with skin and has a rich blood supply
how many columns does the CC have
two
how many columns does the CS have
one
which lies in between the two columns of CC which contains the urethra
glans
tip which is expanded into a triangular structure
extending part of the CC, semen and urine will leave the external urethral orifice
smegma is secreted within the foreskin, if not cleaned properly this can build up and could lead to a potential penile tumour
foreskin
found just above the glans , skin is folded upon itself, forming a movable double layer
arterial blood flow of penis
deep, dorsal and bulbar arteries which are branches from the internal pudenal arteries
venous drainage of the penis
blood is drained to the internal pudenal and internal iliac veins which join to external iliac vein forming the common iliac into the IVC
parasympathetic of penis
filling of blood of the spongy erectile tissue, cause arteriolar dilation and venoconstriction, increasing blood flow into the penis and obstructs outflow
penis becomes engorged and erects
blood vessels dilate, diameter of lumen increases, increasing blood flow into CC. erectile tissue becomes engorged with arterial blood which compresses on the vein maintaining the erection. The CS keeps the urethra open for semen to leave the penis. once it reaches a critical level, stimulation switches to sympathetic
sympathetic stimulation of penis
causes sphincter muscles to contract closing the bladder preventing the reflux of semen. Reproductive ducts contract forcing semen out into the urethra, end point is when the bulbospongious muscles contract forcing the expulsion of semen
corpus cavernosa
forms wing like structures which attaches the penis to the ischium
central artery runs through the centre of the column
corpus spongiosum
extended portion of the penile bulb, keeps the urethra open during ejaculation
extends upwards into the body and distally forming the glans
prostate relations
inf: urinary bladder
rectum sits behind the SV, SV may be included within the TV
prostatic fluid
citric acid: sperm can produce ATP
prostatic enzymes: PSA, pepsinogen, amylase, breaks down clotting proteins released by SV’s
seminal plasmin: antibiotic which prevents UTI
acid phosphate: unknown function
secreted by the prostate, enters the urethra by contractions
helps maintain sperm through semen
prostate structure
true capsule = fibrous lining
false capsule = lies beneath the truth capsule, layer of connective tissue
between the layers are a venous plexus, which drains blood into veins found in the L-spine
mets in L spine are common as blood drains directly into overlaying parts
muscular layer = lots of glandular tissue
peripheral zone is larger in young men which atrophies over time
benign prostatic hypertrophy
compresses prostatic urethra, causing urinary dysfunction
consequence of inflammation or prostatis in the UB or prostate, or due to catherisation
BPH symptoms
nocturne, urgency
psa levels
<4ng/ml = normal
>10ng/ml = prostate cancer
what might be offered regarding PSA as a treatment
AS, with routine blood tests
