229. Histology of Male Repro System Flashcards
Describe sperm transport from interior of testis to ductus deferens
Embryo Development: what gave rise to the testicular stroma, parts of sperm transport?
Testis Interior: Seminiferous tubules = straight tubules = rete testes in mediastinum
Testis Exterior: Efferent ductules = epididymus (head, body, tail) = ductus deferens
Testicular Stroma and Leydig Cells = Intermediate Mesoderm
Primary Sex Cords: surround spermatogonia, give rise to seminiferous tubule epithelium, straight tubule, rete testis
Mesonephric (Wolffian) Duct: efferent ductules, epididymus, ductus deferens
What is the function of Sertoli Cells (6) and Leydig cells?
What steps of mitosis/meiosis occur during spermatogenesis?
What is spermiation?
What is spermiogenesis?
Sertoli cells: blood-testis barrier protect sperm, androgen-protein binding (increase T conc in testis), metabolic support, phagocytosis (remove dead cells), make AMH (trigger male sex differentiation), make molecules to regulate Leydig cell hormones
Leydig cells: produce T b/w tubules (big round nuclei)
Spermatogenesis (74 days)
- Spermatogonia divide by mitosis (connected by cytoplasmic bridge)
- Spermatocytes divide both meiotic divisions into spermatids
- Spermatids undergo morphologic differentiation
Spermiation: release of sperm to lumen (300M/day)
Spermiogenesis: morphological transformation
- ACROSOME: vesicle of enzymes, enlarges to surround nucleus (Fx to degrade zona pellucida for oocyte penetration), centriole initiates formation of AXONEME of microtubule doubles of flagellum, sheath of mito wraps around proximal axoneme (middle piece), fibrous sheath around rest of tain (Principal piece)
Histo of
- rete testis
- epididymus (how long for sperm passage?)
- ductus deferens
Rete testis: simple cuboidal epithelium ducts with veins (simple squamous), straight tubules with sertoli cells join rete testis (close to seminiferous tubules)
epididymus: pseudostratified columnar epithelium, adipose tissue, smooth m, cilia, coiled ducts with stereocilia principal cells, basal cells are stem cells (sperm acquire mobility in epididymus with high cAMP, Ca, phosphorylation); takes 12 days to pass
ductus deferens: pseudostratified columnar epithelium with stereocelia, THICK 3 muscle layers (inner long, middle circular, outer long)
Spermatic cord: Ductus deferens, pampiniform veins (plexus to regulate head, counter current heat exchanger), testicular arteries
What are the steps of Ejaculation?
When do sperm get the ability to fertilize egg? What is this called?
What is the Acrosome rxn with the Zona Pellucida?
- Contraction of bulbourethral glands for lubrication (begins in foreplay)
- Contraction of ductus deferens to move sperm to urethra (EMISSION) - symp control (tube contraction)
- Contraction of prostate - secretions liquefy semen after ejaculation (mobilize sperm in vagina)
- Contraction of seminal vesicles - add fructose to nourish sperm/add bulk/viscosity
- Powerful contraction of bulbospongiosus m (striated = pudendal nerve) in penis to ejaculate semen
Capacitation: in female internal genital tract, glycoproteins removed from head of sperm to be able to fertilize ovum
Acrosome rxn: release of acrosome hyaluronidase and proteases in zona pellucida to help sperm penetrate
Zona pellucida blocks sperm by Fast block (depolarize cell membrane = electrical block) and Slow block (cortical degranulation and protein cross-linking = harden zona pellucida = mechanical block)
Prostate
- what are the zones and sites of cancer
- histo
- markers in serum
Seminal Vesicles
- histo
- fx
Transitional/periurethral zone: site of benign tumor (BPH)
Peripheral Zone: site of malignant cancer
Central Zone: surround ejaculatory ducts, tumor resistant
Prostate: pseudostratified columnar epithelium in glands, fibromuscular tissue septa b/w glands, PROSTATIC CONCRETIONS (calcified/hyaloid material - concentric rings)
PSA/PAP fx to liquefy semen after ejaculation, if high in serum can use to monitor PCa
Seminal Vesicles: short psudostratified columnar epithelium, ONE CONTINUOUS LUMEN, fx: nourish sperm with fructose
Bulbourethral Gland
- fx/histo
Penis
- types of erectile tissue and what runs through them
- mechanism of erection
Bulbourethral gland
- corpus spongiosum: contains urethra (contracts to ejaculate)
- Corpus cavernosum (2): contain deep artery of penis (most important for erection)
erection: parasymp ACh = more Endothelial NO = more smooth muscle cGMP = deep artery VD & relax sinusoids = erection (viagra inhibits cGMP degradation = prolongs erection)
