Male
reproductive organ
•
Epididymis
•
It is a coma-shaped body situated along the lateral
part of the posterior border of testis
•
It is an organ that contains the efferent ductules and
the duct of the epididymis
•
The efferent ductules are lined with pseudostratified
columnar epithelium
•
A circular smooth muscle layer 1st appear at the
beginning of the efferent ductules
Duct of epididymis
•
It is lined with a pseudostratified columnar
epithelium. It contains principal cells and basal cells
•
Numerous long, modified microvilli called stereocilia
extend from the luminal surface of the principal cells
•
Epididymal cells function in both absorption and
secretion
•
The smooth muscle coat of the duct of epididymis
gradually increases in thickness to become three-layered in the tail
Ductus deferens
is a thick cord-like tubular structure and is about 45 cm. it is lined by
pseudostratified columnar epithelium with stereocilia and a lamina
propria. The thick outer wall is formed by inner and outer longitudinal and
middle circular smooth muscle cells layers.
.
§ SN: In epididymis, the lumen is smooth but in d. deferens the lumen is
thrown into deep longitudinal fold due to contraction of the thick muscular
coat.
Course and
relations of ductus deferens
•
It begins from the tail of epididymis then enters the
spermatic cord and traverses the inguinal canal
•
At the deep inguinal ring the vas leaves the other
constituents of the cord & ascend in front of the external iliac artery
•
Next the vas crosses above and medial to the terminal
part of Ureter & passes behind the base of urinary bladder
•
Finally, approaches the base of prostate and joins
with the duct of seminal vesicle to form the ejaculatory duct
Seminal vesicle
• They are paired, elongated and highly folded tubular glands
• It secrete a fluid rich in fructose which is the principal metabolic
substrate for sperm
• It is lined by pseudostratified columnar epithelium which contain tall,
nonciliated columnar cells and short, rounded cells that rest on basal lamina
Prostate gland
•
This is a pyramidal-shaped, fibromuscular and
glandular organ 3cm in long, which surrounds the prostatic urethra
Prostate gland: relations
•
Superiorly: it is continuous with the neck of urinary
bladder
•
Inferiorly, the apex of the prostate rest on external
sphincter of the bladder
•
Anteriorly, lies the pubic symphysis separated by the
extraperitoneal fat of retropubic space
•
Posteriorly,lies the rectum separated by the fascia of
Denonvilliers
•
Laterally, lies levator ani
The prostatic capsules
•
These are normally two
•
The true capsule – a thin fibrous sheath
which surrounds the gland
•
The false capsule –condensed extraperitoneal
fascia
• Between
layers 1 and 2 lies the prostatic venous plexus
•
In prostatic operation the true capsule is not
disturbed because the prostatic venous plexus lying external to this.
The
prostate gland secretes prostatic acid phosphatase (PAP), fibrinolysin, citric
acid & prostate specific antigen
Presenting parts of prostate
•
The apex is directed below
•
The base is directed above
and surrounds the neck of the bladder. It is pierced by the urethra in the
median plane
•
Anterior surface is narrow
and convex situated behind the lower part of symphysis pubis
•
Each infero-lateral surface
is related to the anterior fibers of the levator ani
•
The posterior surface is
broad and flat related to the ampulla of rectum. This surface is palpable by
rectal examination about 4 cm.above the anus.
The penis
•
It forms the male organ of
copulation and consists of two parts – a root and a body
•
The root is situated in the
superficial perineal pouch and consists of two diverging crura and a median
bulb of the penis
The body of
the penis
• The
body of the penis consists principally of two dorsal masses of erectile tissue
the corpora cavernosa which are the continuation
of two crura and a ventral mass of erectile tissue the corpora spongiosum in
which the spongy part of urethra is embedded and it is the continuation of bulb
of penis .
CORPORA CAVERNOSA
•
It is divided into number of
intercommunicating cavernous spaces which is lined by endothelium
•
These spaces receive the
blood from the capillaries of the helicine arteries are the branches of deep
artery of penis
•
During erection the
arterioles dilate and the cavernous spaces are filled with blood, at the same
time the venous outflow is diminished by the pressure of the distended
cavernous spaces. Therefore, erection is purely a vascular phenomenon
Coverings
of penis
•
The skin
•
The superficial fascia
•
Fibrous envelope- the tunica
albuginea
Ligaments of penis
•
Fundiform ligaments
•
Suspensory ligaments
•
Erection
•
It is a vascular phenomenon which occur by
the action of parasympathetic nerve. The parasympathetic nerve ( S2-4 spinal
segments) dilate arterioles of the corpora cavernosa
•
•
Ejaculation
•
It is stimulated by the
sympathetic nerves (L1 spinal segment) which produce contraction of the vas
deferens, seminal vesicle, ejaculatory ducts and prostate.
•
Contraction of the internal
urethral orifice preventing the reflux of semen into the bladder
•
At the end of the ejaculation, the sympathetic nerves produce
vasoconstriction of penis and the penis is flaccid.
The parasympathetic initiates the sexual act by erection &
sympathetic finalizes the act by ejaculation
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