This document summarizes the roles and actions of the gonadotrophins FSH and LH in females. It describes their chemical structure as glycoproteins composed of alpha and beta subunits. FSH stimulates follicular development and estrogen production by granulosa cells. LH triggers ovulation and corpus luteum formation, supporting oocyte maturation and progesterone secretion. Both FSH and LH act through G-protein coupled receptors in theca and granulosa cells to regulate steroidogenesis and gene expression critical for female reproductive functions.

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 