Male reproductive physiology Flashcards
What hormones are synthesized in testes?
Testosterone and Inhibin
Testosterone inhibits secretion of which hormones? (negative feedback)
GnRH and LH
Estradiol and Inhibin inhibit secretion of which hormones?
GnRH and FSH
Hypothalamic-Pituitary-Testicular axis has a role in what processes?
- Phenotypic gender
- Sexual maturation (puberty)
- Testosterone production
- Sperm production
What are the two genetic sexes?
XX; XY
What are the two different gonads?
Testes; Ovaries
What determines the phenotypic sex?
Internal and external genitalia
What has to be present in order for male phenotypic sex to develop?
Antimullerian hormone and testosterone
Absence of antimullerian hormone and testosterone leads to development of which phenotypic sex?
Female
Which cells in testes produce testosterone?
Leydig cells
Which cells in testes produce antimullerian hormone?
Sartoli cells
Which hormone is responsible for development of male external genitalia?
DHT
Which enzyme converts testosterone into DHT?
5-a-reductase
What are the male external genitalia?
Prostate, penis, scrotum
What are the male internal genitalia?
Seminal vesicles
Vas deferens
Epididymis
Ejaculatory ducts
Which hormone is responsible for the development of male internal genitalia?
Testosterone
What is the sex genotype of individuals with Androgen Insensitivity Syndrome?
XY
What gonads do individuals with Androgen Insensitivity Syndrome have?
Testes
Which condition is described with absent testosterone receptors?
Androgen Insensitivity Syndrome
Due to lack of testosterone receptors, individuals with androgen insensitivity syndrome do not develop what structures?
male external and internal genitalia
Do people with AIS have antimullerian hormone and testosterone?
Yes, they have testes
Presence of antimullerian hormone and testosterone lead to absence of which structures in individuals with AIS even though they are phenotypically female?
Fallopian tubes, uterus, upper vagina
What kind of external genitalia do individuals with AIS have?
Female (default): short vagina, labia, clitoris
Individuals with AIS even develop breasts during puberty. Why do they have female secondary characteristics?
Too much testosterone which gets converted into estradiol.
What structures make 80% of testes?
Seminiferous tubules
What do seminiferous tubules produce?
Sperm
What cells are present in seminiferous tubules?
Sartoli cells (supportive)
Spermatogonia (stem cells)
Spermatocytes (developing sperm)
What makes 20% of testes?
Connective tissue (interstitium)
What cells are present in the interstitium of testes?
Leydig cells Mast cells Macrophages Nerves Blood vessels Lymphatics
What do leydig cells produce?
Testosterone
What hormone from pituitary stimulates Leydig cells?
LH
What hormone from pituitary stimulates Sartoli cells?
FSH
