gonadotropins

1. GONADOTROPHINS

2. CHEMICAL STRUCTURE OF FSH & LH
 Water soluble glycoprotein
 Molecular weight:30,000 Daltons
 Protein molecule with a sugar attached to it
 Protein dimer contain two polypeptide
unit:alpha & beta subunit

3. HORMONE SYNTHESIS

4. ACTION OF FSH AND LH IN
FEMALES
 Estradiol production
 Follicular development
 Cellular action of FSH and LH
 Effects on ovulation
 Effects on corpus luteal formation
 Oocyte maturation
 Corpus luteal funtion
 Ovarian blood flow

5. LH FSH
Cholesterol
Pregnenolone
17 – OH Progesterone
Androstenedione
Oestradiol
Cholesterol
Pregnenolone
Androstenedione
Oestradiol
THECA CELL GRANULOSA CELL

6. FOLLICULAR DEVELOPMENT
 Influences proliferation and development of
granulosa cells
 Follicular phase divided into 3 phases
Early
Mid follicular
Late follicular
 At the end of this phase large no of granulosa
cells are present
 Which then produce sufficient estradiol

7. CELLULAR ACTONS
 Both binds G-protein coupled receptors n
granulosa and theca cells
 Activates adenyl cyclase increases the
expression of p450c17
 Increased concentratin of cyclic AMP
activates protein kinase
 Which catalyses phosphorylation of CREB
and other plasmic proteins transcription
of genes

8. OVULATION
 LH is the physiolgical signal for ovulation
 Events of follicular rupture are initiated by
production of cyclicAMP in response to LH
 Plasmin accumulates in the follicular fluid and
produces plasminogen
 Granulosa cells secreates plasminogen
activator
 Cells begin to secrete progesterone
 Aromatase activity gets lost

10. CORPUS LUTEUM FORMATION
 LH plays an important role
 The lutein cells secrete large amount of
progesterone and less estrogen
 Progesterone secreted have a strong
negative feedback on anterior pituitary to
decrease FSH and LH

11. OOCYTE MATURATION
 Granulsa cells prevent the ovum from
completing its mieotic division by a substance
oocyte maturation inhibitor
 LH triggers the resumption of mieosis by
blocking the production of this factor

12. OVARIAN BLOOD FLOW
 LH increases the blood flow to the ovary and
produces ovarian hyperemia

13. DISORDERS
Precocious puberty
Delayed or absent puberty
Infertility
Amenorrhea

14. THANK U 