Histology of male reproductive system (basic) Flashcards
where do the testis lie?
in the scrotum
what are the testis composed of?
seminiferous tubules that drain into the rete testis
what do the rete testis then lead to?
the efferent ductules which then lead to highly coiled epididymus and then vas deferens
what is the testis surrounded by?
a heavily vascularised tunica vasculosa and then a tough CT of tunica albuginea (capsule)
what is each seminiferous tubule surrounded by?
perilobar CT as well as Leydig cells between them
what are Leydig cells’ homologous in female?
theca cells of ovary
both function to produce androgens
what are testosterone (androgens) produced from in the testis?
circulating cholesterol
what are seminiferous tubules each lined with?
cells of different morphologies - various stages of developing male gametes
(spermatogonia, spermatids, spermatozoa)
where are spermatogonia located within the lining of seminiferous tubules?
deepest to the tubular wall
how do spermatogonia turn into spermatids and spermatozoa?
spermatogonia slowly migrate to the lumen (of ST), to develop into spermatids, then spermatozoa
what envelops developing spermatozoa?
Sertoli cells
what is the homologous of Sertoli cells in females?
granulosa cells
both responsive to FSH levels
what is the function of Sertoli cells in males?
responsible for metabolic and structural support of the developing spermatozoa
what do Sertoli cells produce?
the blood-testis barrier of the testis
also produce inhibin
what else surrounds the seminiferous tubule within the testis? function?
myofibroblast
exhibit contractile function
when do testicular tumours occur? which type is most common?
occur in early life (not common age group for tumours)
90-95% = germ cell tumours
where do spermatozoa formed in the seminiferous tubules pass via? into?
via straight tubules into rete testis
what do the channels of rete testis fuse to form?
a number of efferent ductules - which drain into highly coiled epididymus (H,B,T)
what do efferent ductules connect?
rete testis to head of epididymus
what is efferent ductule lined with?
loose CT and a mixture of columnar and non-ciliated cuboidal cells
what is the function of non-ciliated cuboidal cells within the efferent ductules?
reabsorb some of the fluid produced from the seminiferous tubules
what is the function of the columnar cells within the efferent ductules?
move sperm through the seminiferous tubules
what else lines the efferent ductules?
contractile cells
function of contractile cells lining the efferent ductules?
adding to sperm transport
describe the epididymus
coiled tube with head, body, tail
what lines the epididymus?
pseudostratified epithelia containing stereocilia
what does the lining of pseudostratified epithelia containing stereocilia allow for in the epididymus?
reabsorption of any residual bodies of sperm lost during maturation and modulation of any secretions
what surrounds the tubule of the epididymus? what does it allow for?
substantial muscular layer surrounding tubule, allowing for rhythmic contraction in the head and body of the epididymus
what type of control is the tail of the epididymus under?
autonomic control
what is the function of the vas deferens?
transports male germ cells from epididymus to the ejaculatory duct
where is the ejaculatory duct formed?
at the union of the seminal vesicle and terminal part of the vas deferens
what does the vas deferens contain? function?
an extremely thick muscular layer made of 3 separate muscular layers (outer longitudinal, middle circular, inner longitudinal)
for powerful contractions
what is the folding of the mucosal layer of the vas deferens due to?
tone of the (middle) circular layer of SM
what is the epithelial lining of the vas deferens?
pseudostratified with a few stereocilia present (same as epididymus, but less stereocilia)
what are the seminal vesicles?
paired glands open into vas deferens near prostatic urethra
what do seminal vesicles initially develop as?
outgrowing of the vas deferens
what are each seminal vesicle like?
coiled tubulosaccular glands
what is the mucosa of seminal vesicles like?
mucosa is highly folded and surrounded by a muscular coat
what is the innervation of the muscular coat surrounding the seminal vesicles?
sympathetic
what is the function of the seminal vesicles?
provide bulk of the ejaculate
where are the prostate glands located?
surrounds the prostatic urethra at the base of the bladder
what do the prostate glands consist of?
3 tubuloalveolar glands arranged around the urethra:
mucosal, submucosal and main glands
(also = central, transitional, peripheral zones)
what do the 3 tubuloalveolar glands of the prostate drain into?
the urethra
what is the prostate surrounded by? forming?
a fibromuscular capsule, from which the septae form
what is the function of the septae (from fibromuscular capsule) in the prostate?
divides the prostate up into zones
what does the prostate produce? function?
a slightly alkaline fluid
helps to neutralise acidity of the vaginal tract
which epithelia lines the prostate?
heterogenous epithelia - so can be: simple squamous cuboidal columnar OR pseudostratified
what can occur to the prostate in older men?
enlargement of the prostate (PH)
benign (BPH) / malignant (MPH)
what causes enlargement of the prostate?
bodies of proteins, cholesterol and calcium phosphate can calcify and form in the ducts
what are the most common disorders of the prostate?
hyperplasia and carcinoma
where is BPH most commonly seen?
in transitional zone
where is prostatic adenocarcinoma most commonly seen?
in peripheral zone
how do BPH and prostatic adenocarcinoma present?
similar symptoms:
frequency
urgency
incontinence
when do symptoms of prostatic adenocarcinoma present?
present late as it is in the peripheral zone - doesn’t compress prostatic urethra as early on as BPH in transitional zone
what are the bulbourethral glands?
2 small exocrine glands that are found exiting the membranous portion of the urethra at the base of the penis
what is the function of the bulbourethral glands?
produce ‘pre-ejaculate’ for lubrication
