Male Repro Flashcards
(27 cards)
Products of Sertoli cells
Inhibin: inhibits release of FSH
Activin: promotes release of FSH
AMH: ensure Wolffian duct will form
ABP: binds testosterone to keep it high in seminiferous tubules for the production of
Form blood testes barrier
Prostate Cancer
Prostate relies entirely on DHT
Therapies involve reducing the amount of testosterone produced:
-5alpha reductase (converts testosterone into DHT) when the tumor is androgen dependent
-GnRH agonist/antagonist
-Glucocorticoids
-CYP17 inhibitor
-AR antagonist
-estrogen treatment (to downregulate the pulse generator)
5 alpha reductase
Converts testosterone into potent DHT in peripheral tissues, specifically the external genitalia
DHT is more potent because
Has higher affinity for AR than testosterone
Function and location of Blood Testes Barrier
Made by tight junctions of adjoining Sertoli cells-below are spermatagonia and above are primary spermatocytes
- Prevent harmful substances from contaminating fluid around sperm
- Prevent sperm from entering blood stream (which could elicit an immune response)
- Maintain high testosterone locally
Significance of 17-HSD
Only found in Leydig cells
Serves to convert androstenedione into testosterone
Expression of CYP19 in males
Primarily found in Leydig cells and peripheral fat to convert androstenedione/testosterone into estrone/estradiol
Sperm stem cells
Spermatagonia
Kartagener’s Syndrome
- immotile cilia syndrome
- cilia lack dynein in order to function
- males are sterile
- also suffer chronic sinusitis and bronchitis
Effect of FSH
- acts on seminiferous tubules to increase spermatogenesis
- acts on Leydig cells to increase their sensitivity to LH
Effect of LH
Stimulates Leydig to produce testosterone
Mechanisms for temperature regulation of testes
- Countercurrent heat exchange with papiniform plexus
- Dartos smooth muscle and cremaster skeletal muscle
Controlled by ANS
Pathway of testicular duct system
Seminiferous tubules–>straight tubules–>rete testis–>efferent ductule–>epidymis–>vas deferens–>ampulla (storage)–>ejaculatory duct
–>urethra
Epididymis
-where spermatozoa acquire motility
3 parts of the male urethra
- Prostatic
- Membranous
- Spongy
Seminal vesicles
- Very coiled, but actually only one
- Goblet cells
- Produces majority of semen, include fructose needed to nourish sperm
Benign prostate hyperplasia
- enlargement of prostate due to an increase in the number of cells
- linked to DHT formed by 5alpha-reductase
- usually at the transition zone (around the urethra close to the ejaculatory ducts), which causes issues with urination
Erection
- ateriovenous anastomosis closed (these are normally open in a flaccid penis) so that erectile tissue can be filled
- filling of veins
- blood outflow reduced because of Buck’s fascia; raises penis to erect position
- nitric oxide causes relaxation of smooth muscle of erectile tissues (this is the target of ED drugs…prolong the action of NO)
- PARASYMPATHETIC
Nervous System-Ejaculation
-SYMPATHETIC
Capacitation
The process by which sperm are altered by the female reproduction system in order to be able to fertilize the egg
Involves removing sperm glycoprotein coat and proteins
Kleinfelter’s
47, XXY
Elevated gonadotropes, low testosterone
Impaired spermatogenesis
Impaired male sexual development (small penis, weak muscle tone, sparse facial and torso hair)
XX Male
Due to a fragment of SRY translocated onto the X chromosome
Presents like Kleinfelter’s
Duplicated SOX9
Complete Androgen Resistance
46 XY Genetically male, but phenotypically female Androgen receptor on X-chromosome No Wolffian duct formation Regression of the Mullerian duct No DHT function Testes still generating testosterone but receptors aren't working, so it is converted to E2 Male pseudeohermaphroditism
Reifenstein’s Syndrome
Partial androgen resistance
Androgen receptor on X chromosome
Broad spectrum of secondary sex characteristics with ambiguous genitalia
Severity depends on the amount of resistance
