Final Exam Flashcards
What maintains testicle temperature of 34°C?
• pampiniform plexus
• spermatic cord cremaster muscle
• scrotum dartos muscle
What is the abdominal peritoneal process that covers the tunica albuginea?
Tunica vaginalis: sac that surrounds anterior and lateral parts of the testes.
What is the tunica albuginea?
Blue gray fibrous membrane that covers the testis. Septa divides lobules and mediastinum of testes
What are the components inside of the tunica albuginea?
1. Seminiferous tubules
• Sertoli cells (endocrine, inhibin)
• germ cells (exocrine, sperm)
2. Interstitial connective tissue
• peritubular myoid cells (contractile smooth muscle)
• interstitial cells of Leydig (endocrine factors- steroids, testosterone)
What is the spermatogenic wave?
• spermatogenic cells replicate and differentiate into mature sperm in waves throughout different portions of the seminiferous tubules
What is spermatogenesis?
The formation of spermatozoa from spermatogonia
What is spermiogenesis?
The last stage of spermatogenesis which includes the maturation of the spermatozoa and acquisition of motility
What are the three classes of spermatogonia?
- Dark type A (reserve stem cells)
- Pale type A (renewing stem cells)
- Type B (differentiating progenitors)
What are the four phases of spermiogenesis?
- Golgi: Golgi become acrosome, axoneme formed, centriole forms manchette
- Cap: acrosomal vesicle forms (Will breakdown Zona pellucida of ovum)
- Acrosomal: head of sperm forms and orients towards base of seminiferous tubule
- Maturation: residual bodies shed, spermiation (release of sperm ) occurs
Spermatozoa anatomy
What are Sertoli cells?
• true epithelial cells of the seminiferous tubules
• they formed the blood testes barrier with tight junctions
What type of receptors are on Sertoli cells?
FSH receptors: they produce androgen binding protein (ABP) and inhibin
What are the interstitial cells of Leydig?
• compact groups of cells with large, eosinophilic cytoplasm and round nuclei. Extensive smooth ER
• may have crystalloid inclusions (Reinke crystals)
• steroid/ testosterone production
Estrogen promotes what in the testes?
Spermatogenesis and sperm maturation (Sertoli, leydig, and germ cells all express aromatase to convert testosterone to estrogen)
Are leydig cells temperature sensitive?
No, therefore cryptorchidism has no effect on androgen output (only affects sperm production)
What is the rete testis?
• labyrinth plexus of epithelially-lined channels in the mediastinum of the testes (simple cuboidal cells)
What types of cells line the efferent ductules of the testes?
Simple columnar epithelium— alternation of tall cells (ciliated) and short cells (microvilli)
What are the cells composing the epididymis?
• pseudostratified columnar epithelium:
- Principal cells containing stereocilia
- Basal cells that act as stem cells
What is the Vas deferens?
• Long, very thick muscular wall that runs through the spermatic cord containing arteries, veins (pampiniform), lymph vessels, nerves, skeletal muscle (cremaster)
• composed of pseudo stratified columnar epithelium with stereocilia
• three muscular layers: inner longitudinal, middle circular, outer longitudinal
What are the seminal vesicles?
• unbranched tubular diverticulum of the distal end of the vas deferens
• composed of mucosa creating cavities, epithelium (columnar) containing clumps of yellow lipochrome pigment
• dependent on testosterone levels
What is the purpose of the Seminal vesicles?
• secretion of fluid high in fructose, ascorbic acid, prostaglandins, and fibrinogen that contributes 80% of the total volume of ejaculate
The prostate gland is dependent on what for development?
Dihydrotestosterone (DHT)
What are the four zones of the prostate gland?
- Central
- Peripheral
- Transitional
- Periurethral
What are the cells of the prostate?
• highly folded epithelium made of simple cuboidal to simple columnar
• cells contain secretory vesicles and yellowish lipoidal droplets (conceptions)
What is the function of the prostate?
• secretion of a thin, milky, faintly acid fluid for ejaculation
• contains PAP (acid phosphatase), PSA, and proteolytic enzymes
• activity is testosterone dependent
What are the bulbourethral/Cowper’s glands?
• paired bodies that lie in the connective tissue behind the membranes urethra
• sexual arousal causes pre-ejaculation from the glands for lubrication (comparable to Bartholin’s glands)
Anatomy of the penis
Penile erection is caused by what?
• parasympathetic stimulation: smooth muscles dilate, blood flows rapidly into cavernous spaces, venous drainage is reduced, maintains erection
Ejaculation occurs by what nerve?
S2-4 pudendal nerve
What causes detumescence?
Erection termination caused by sympathetic stimulation—> arteries regain tone and venous blood flow can occur
What are the three portions of the male urethra?
- Prostatic
- Membranous
- Penile
What is the purpose of androgen binding protein?
It keeps intracellular and gonadal testosterone high
What are the effects of androgens?
Male characteristics: hair growth, spermatogenesis, libido
What are the anabolic effects of androgens?
Promote cell growth: bone growth, RBC growth, muscle growth
A high androgen to anabolic ratio is a good medication for what?
• hormone replacement therapy
• hypogonadism
• trans men
A high anabolic to androgen ratio as a medication is good for what?
• anemia (RBC increase)
• osteoporosis
What types of medications are used to support fertility in men?
• androgens with a high androgen: anabolic ratio
• pulsatile infusion of GNRH agonist to promote FSH/LH
• FSH/LH injections to promote testosterone and spermatogenesis production
What drugs are used for chemical castration?
• androgen antagonist to block testosterone action
• GnRH agonist, continuous non-pulsatile also suppresses testosterone
What is used as a medication to promote hair follicle growth?
5-Alpha reductase inhibitors to suppress ditestosterone production
What medications are used for prostatic hyperplasia?
• 5-Alpha reductase inhibitors
What is a drug used for erectile dysfunction?
Phosphodiesterase-5 inhibitors (PDE5 inhibitors) to inhibit cGMP
What is Dagarelix?
GnRH antagonist
What are leuprolide, gonadorelin, and goserelin?
GnRH agonists: activating when pulsatile, inhibiting when continuous
What are finasteride, dutasteride?
5-Alpha reductase inhibitors
What are the PDE5 inhibitors?
Sildenafil, tadalafil, and vardenafil
What drugs are androgen antagonists?
• bicalutamide
• flutamide
• nitulamide
• apalutamide
• enzalutamide
What drugs are general steroidogenic inhibitors?
• ketoconazole
• aminoglutethimide
• spironolactone