L41 42 Male reproductive Flashcards
Tunica albuginia of testes and contents of testes
dense connective tissue layer around testis
thickens posteriorly forming mediastinum testis
connective tissue septa radiate from mediastinum testes making lobules
- each lobule contains several highly coiled seminiferous tubules responsible for spermatogenesis and lined with epithelium
- spermatogenic cells make sperm
- sustentacular cells provide support by secreting fluids that carry spern to the rete testes within the mediastinum testes
seminiferous tubules
surrounded by interstitial tissue containing INTERSTITIAL CELLS of LEYDIG that are responsible for steroidogenesis (androgen and testosterone in fenestrated caps)
LOOK AT IMAGES
rete testes and efferent ducts
composed of flat interconnected channels lined by cuboidal cells with single cilium to transport sperm to efferent ducts.
- efferent ducts contain COLUMNAR ciliated cells but also cuboidal cells with microvilli (reabsorbtion of excess fluid)
- carried from efferent ducts to epididymis and stored until ejaculation
LOOK AT IMAGES
Spermatogenesis
occurs in seminiferous tubules surrounded by BM and thin tunica propria with scattered myfibroblasts
happens from puberty to death
sperm spends 74 days in testes and 12 days in epididymis to reach maturity
(86 days for antispermatogenic agent to cause observable problems
spermatogenesis slide
spermatogonia type A and B
primary spermocytses
secondary spermocytes
-M2
spermatozoa (spermiogenesis-differentiation of sperm)
-spermatogonia-nuclei along BM
-primary spermatocyte: checkerboard nucleus
-spermatid: (haploid) small dark nucleus near lumen
-spermatozoon (mature sperm IN LUMEN)
HISTO SLIDE 7
Blood/testes barrier
formed by tight junctions between sustentacular cells
divides seminiferous epithelium into a basal compartment and luminal compartment
prevents antibodies from targeting immature sperm
traps testosterone in luminal compartment
-required for spermatogenesis
separates the secretions of the sustentacular cells
sustentacular cell secretions
secretions to luminal compartment:
- Fructose rich fluid (nourishment/transport)
- ABP-binds to testosterone and traps it in the lumen to maintain spermatogenesis. Secreted in response to FSH (from where)
secretions to interstitial space
- mullerian inhibiting substance (MIS)- establishes “maleness” of embryo by inducing degeneration of mesonephric duct ducts during prenatal development: onset of puberty too
- inhibinL inhibits spermatogenesis by inhibiting FSH
Hormone expression for spermatogenesis
Lh secreted from anterior pituitary binds to receptors on INTERSTITIAL CELLS
LH induces the interstitial cells to secrete TESTOSTERONE that enters the luminal compartment and fenestrated caps
FSH from anterior pituitary binds to receptors on SUSTENTACULAR CELLS
FSH induces sustentacular cells to secrete ABP into luminal compartment
ABP binds to testosterone and prevents it from leaving the luminal compartment
RESULT: elevated testosterone levels in luminal compartment maintains spermatogenesis
slide 13 feeback loops
Epididymis
single highly coiled tube that stores sperm prior to ejaculation
gain motility here but moved by peristalsis
lined with PSEUDO STRAT COLUMNAR EP with Stereociliated (aids secretion and absorbtion/phag) PRINCIPAL CELLS
Principal cells: secrete decapacitation factor
-resorb excess fluid in lumen
-phag residual bodies (excess sperm cytoplasm shed during spermatogenesis)
Ductus Deferens and Vasectomy
-histologically can see spermatic cord vessels
Conducts sperm from ejaculatory duct during ejaculation
VERY THICK LAYER SMC
PSEUDOSTRAT COLUMNAR w/ Stereociliated principal cells
Vasectomy
less common than bilateral tube sterilization in females
SURGICALLY REVERSIBLE
Basal cells (stem cell of ep), SMC (reg), and Stereocilia (increase SA for rapid phag of materials including fluid and debris from inflamm and trauma) all contribute to regeneration post op
urethra and infection
Prostatic: TRANSITIONAL EPITHELIUM
membranous : STRAT COLUMNAR
Distal/penile: STRAT SQUAMOUS
acute bacterial urethritis- inflammation from infection
- bacteria enter transcellularly
- ghonnorhea and clam invade epi cells and live in them
common UTIL staph sapromyticus adheres to PM of epi, can spread retrograde to prostatitis epididymitis
Penis, erection, CT of penis
corpus spongiosum
2 corpora cavernosa
-both vascular spaces lined with endothelium
-erectionL PS impulses constrict arteriovenous shunts and dilate helicine arteries increasing blood flow to the vascular space
CT layers of penis
- tunica albuginia (DEEP)
- bucks
- superficial
seminal vesicles
coiled tubular gland, secretes in ejaculatory duct
- lined by HIGHLY FOLDED mucosa (THREE OR MORE) creating MUCOSAL CRYPTS
- increases the surface area for secretion
- fructose rich (nourish sperm)
- yellow pigment (UV protection)
- 70% of semen volume
Prostate gland function and ZONES
numerous secretory units, each with duct hat secretes directly to the prostatic urethra
- serious enzyme rich semen anticoagulant
- prostatic specific antigen (PSA)
- Prostatic acid phosphatase (PAP)
secretions may harned within prostat making prostatic concretions, very diagnostic of prostate tissue
ZONES Transitional -surrounds urethra -site of BPH -urethral compression -stomal cells (convert test to DHT) (increased DHT linked to BPH)
peripheral
- largest zone
- partitioned by septa
- common prostatic adenocarcinoma site
- palpable with diginal rectal exam
Central
-surrounds EJ duct
bulbourethral glands
looksl ike mucus secreting glands
- ducts that open to the penile urethra
- pre seminal mucous fluid that lubes urethra
EJ duct can become obstructed, whats in the semen? nothing from the seminal vesicles, but everything from prostate and cowpers
