male repro Flashcards
primary sex prgan
tetses
Seminiferous Tubules-
Seminiferous Tubules
- Exocrine Function
Germ Cells: Spermatogonia to Spermatozoa
Interstitial Tissue
Interstitial Tissue – Endocrine Function Leydig cells (interstitial cell) Androgen Secretion (mainly testerone)
LH stimulates
LH stimulates synthesis of testosterone
The rate limiting step in synthesis of steroids
The rate limiting step is cholesterol side chain cleavage by the CYP11A1 enzyme
Cholesterol may be synthesized , how?
Cholesterol may be synthesized de novo or imported from plasma.
Androstenedione
Androstenedione (the major source of estradiol in men) may be converted to estrone and subsequently estradiol in peripheral tissue.
Test. is converted in peripheral tissues to
T is converted in peripheral tissues to estradiol & androstenedione.
2 Major Sex Steroid Binding Proteins
Testosterone-Estrogen Binding Protein (TEBG)
[TEBG is also known as sex hormone binding globulin (SHBG)]
Albumin
One low affinity binding site (T 1/2-=1 second)
Normal Distribution in Blood of Males of Major Sex Steroid Binding Proteins
TEBG (30-45%), Albumin (50-68%), Free (0.5-3%)
androgen receptor
both DHT and test. inerct with it
test. has a higher affinity for binding to andRogen receptor than DHT
T/F
FALSE
STEROLI CELLS
Nourish healthy cells & phagocytize damaged germ cells
Synthesize luminal proteins
Maintain tubular fluid
Convert androgens to estrogens
Are site for hormonal modulation of tubular function
what are 3 Sertoli cell products
and
what do they modulate
Sertoli cell products estradiol, inhibin, activin and other proteins modulate leydig cell activity and germ cell function
Leydig cell testosterone modulates
Leydig cell testosterone modulates peritubular & Sertoli cell function
