Lecture 24 Flashcards
What happens if both testes remain in the posterior abdominal wall?
Infertile
What does the Gubernaculum do?
Governs protein GFRP that is tracked to see passage that nerve follows
Well defined series
What are the two stages of testes development?
- Intra-abdominal - 7 months gestation
2. Outer-abdominal - most cases testes go down to scrotal sac
What is the ductus deferens?
Tubular system
What is the common cancer in young men?
Testicular cancer
- lymph nodes in posterior abdominal wall swell
- lymph nodes in groin area
- if caught early enough can be treated effectively
What forms the perineal region?
Prostate - naturally grows then overgrows
Prostatic hyperplasia
- can compress urethra
- common for older men to go to the bathroom more frequently
- - not abnormal - benign prostatic hyperplasia
prostatic cancer is when hyperplasia is malignant
How many regions are there in sperm development?
13
What is the Tunica vaginalis?
Membrane covering testes
Mesentry that was in anterior wall moves to scrotal sac
Invisible
Tube that connects testes to abdomen
tube seals off mostly (can be hydroseal if not sealed off - fluid retention)
What is the Mediastinum testes?
Midpoint
Where all ducts go through and leave epididymis
What is the septa?
250 lobules each with 1-4 seminiferous tubules
- epithelial lines in between lobules of testes
What is the rete testes?
Connected are straight tubes
Connect to seminiferous tubules
Efferent ducts to epididymis
- Sperm are still immotile at this stage
- Pushes immotile sperm into epididymis
- Epididymis to single ductus deferens (sperm must stay here for 3 days before ejaculation to become motile)
What forms the seminiferous tubules?
Seminiferous epithelium, surrounded by myoid cells (peritubular contractile cells: actin)
What are myoid cells?
Has myosin and actin so can contract but looks like epithelium
Without contraction sperm cannot become motile - infertile
What coiled loops lead to?
Rete testes
How long can seminiferous tubules be?
80cm long and 150-250 micrometers in diameter
What do seminiferous tubules do?
Can produce millions of sperm because of long length of seminiferous tubules
Inner side of wall of tubule are made of sertoli cells, lining outside are peritubular cells
Most have a permanent seal around epithelial layer as sperm can be destroyed by his own antibodies
- infertility
What are Sertoli cells?
Non-proliferative, tall simple columnar epithelial cells that extend from basal lamina to lumen
Provide nutritional and mechanical support to germ cells
Phagocytic
How are sertoli cells steroidogenic?
Minor role in synthesis of C21 to testosterone
What do sertoli cells secrete?
Fluid, proteins e.g. transferrin, inhibin, Androgen Binding Protein
What are sertoli cells sensitive to?
FSH
What are features of Leydig cells?
20 micrometers in diameter
Polyhedral cells in connective tissue between seminiferous tubules
Cell surface has microvilli and lots of SER
- steroid handling has very well developed SER
Produces testosterone under influence of LH
- has receptor for lutenizing hormone
What are factors influencing testicular function?
heat
age
irradiation
vasectomy
How does heat affect testicular function?
Cryptorchidism
- when men have testes in abdominal wall and not scrotal sac
How does vasectomy affect testicular function?
Cutting ductus deferens
Doesn’t prevent accessory gland function but sperm are not produced however sperm can be ejaculated up to 6 months after a vasectomy so protection should be used until then
What is the volume of semen?
3.4 +/- 1.6 ms
What is the pH of semen?
7.35 - 7.5
Complex fluid can counteract acidity of urine of being slightly alkali
What does ejaculate consist of?
1. Bulbourethral gland Makes most of urine Sialproteins (pre-ejaculate) 2. Prostate Acid phosphatase (marker of prostate) 3. Testicular Sperm 4. Seminal vesicles Fructose (sperm use fructose as energy source during capacitation) High K Prostaglandins
There is a type of contraception that prevents sperm from entering the egg by…?
membrane becomes thicker
How often can sperm head defects be found in male infertility?
25%