1. Functions of ovarian hormones

2. Ovarian hormones Estrogens Progestins
3 estrogens are produces in significant quantities from the ovaries
β-estradiol
Estrone
Estriol
β-estradiol is the most abundant and potent
Progestins
Progesterone
17-α-hydroxyprogesterone
Progesterone is the most potent and abundant

3. Ovarian hormones

4. General functions ovarian hormones
Functions of estrogens
Proliferations and growth of endometrial cells
Development of secondary sex characteristics of female
Onset of labor
Functions of progestins
Preparation of uterus for pregnancy
Maintenance of pregnancy
Preparation of breast for lactation

5. FUNCTIONS OF ESTROGENS

6. Functions of estrogens
Enlargement of sex organs
At puberty the female sex organs change to adult shape and size
Ovaries
Uterus
2-3 fold increase in size
Monthly endometrial growth
Fallopian tubes
Vagina
Vaginal epithelium changes from cuboidal to stratified type
External genitalia
Deposition of fat in mons pubis and labia majora

7. Functions of estrogens
Uterus
Proliferative phase of endometrial cycle
In pregnancy has important effect on myometrium
↑ gap junctions between myometrial cells
↑ contractility of the myometrium
↑ Braxton Hicks contraction
Helps the onset of labor

8. Functions of estrogens
Fallopian tubes
Effects similar to the effects in endometrium
Proliferation of all the lining cells
Proliferation of glandular tissue
↑ No of ciliated cells
↑ activity of cilia - beating toward the uterus
Help the propagation of fertilized ovum towards the uterus

9. Functions of estrogens
Breast
Development of the stromal tissue
Growth of extensive ductile system
Deposition of fat
Very slight development of lobule and alveoli
(this is brought about by progesterone and Prolactin)
Characteristic growth and external appearance
Male breast can also develop similarly if sufficient female hormones are provided specially up to the age of 20 years

10. Functions of estrogens
Skeleton
↓ osteoclastic activity
↑ osteoblastic activity
Accelerated growth at puberty
Quick union of epiphysis with the shaft of long bones
This effect is stronger than similar effect of testosterone
Absence of ovarian hormones → very tall female eunuchs

11. Functions of estrogens
Skeleton (cont..)
After menopause
↑ osteoclastic activity
↓ osteoblastic activity
↓ bone matrix
↓ Ca and PO4 deposition
Osteoporosis
Weak bones
Easy fracture
Hormone replacement therapy (HRT) does help to prevent or treat osteoporosis

12. Functions of estrogens
Proteins
↑ protein deposition (not very strong effect)
Slight +ve nitrogen balance
Primarily due to proliferation of cells in many female organs and bone matrix formation
Testosterone in male is very strong protein anabolic hormone as compared to estrogen

13. Functions of estrogens
Fats
Deposition of fat in
Most of the subcutaneous fat cells
Breasts
Thighs
Buttocks
Female fat deposition gives characteristic feminine figure to female body
Percentage of fat in female body much more than males
Metabolic rate is increased but not as much as by testosterone in male

14. Functions of estrogens
Hair distribution
No great effect on hair growth or distribution
Pubic hair growth at puberty is also probably due to more androgens from adrenal cortices and may be from theca cells a well
Skin
↑ thickness
Soft and smooth texture
↑ vasularity→
Hyperemic compared to male
↑ Warmth
↑ Bleeding when cut

15. Functions of estrogens
Water and electrolyte
Similar to all steroids
Sodium and water retention by the kidney tubules
The effect is not significant in normal endometrial cycle
In pregnancy this effect becomes important
Very high level of estrogen produces from placenta
Increase in blood volume and salts required during pregnancy

16. FUNCTIONS
OF PROGESTERONE

17. Functions of Progesterone
Uterus
Secretory changes in the endometrium
Glandular growth
Deposition of nutrients in the stromal cells
Secretion by endometrial glands
Preparation for implantation
↓ contractility of the Myometrium
Opposes the contractile effect of estrogen
Prevents the expulsion of implanted ovum
Maintains pregnancy

18. Functions of Progesterone
Breast
Secretory changes
Development of lobules and alveoli
Cells of gland to proliferate and enlarge
Appearance of granules in glandular cells
Swelling due to increased fluid in subcutaneous tissue
Actual milk secretion does not occur
(Prolactin is required for milk secretion)

19. Functions of Progesterone
Fallopian tubes
↑ glandular secretion from mucosal lining
Provides nutrition to dividing fertilized ovum which remains in the fallopian tubes for 3-4 days
Relaxation of muscles of isthmus to allow entry of fertilized ovum into the uterus

20. Functions of Progesterone
Protein
Slightly protein catabolic hormone
Mobilization of amino acids
Important in pregnancy

21. Functions of Progesterone
Electrolytes
Like all steroids electrolyte conservation
Competes with Aldosterone
Far less potent than Aldosterone
Practically causes more loss of sodium
Specially important in pregnancy

22. Endometrial cycle

23. Phases of endometrial cycle
Proliferative phase (Estrogen phase)
Secretory phase (Progestational phase)
Menstrual phase (Menstruation)

24. The Uterine Wall

25. Proliferative Phase
At the beginning of the cycle (after menstruation) endometrium is completely desquamated
Only a thin layer of endometrial stromal cells left
Epithelial cells are present only in remaining deeper portions and crypts of endometrial glands
Follicular phase of ovarian cycle starts secretion of estrogen
The estrogen is responsible for this proliferative phase of endometrial cycle

26. The Endometrial Cycle

27. Proliferative Phase Estrogen (from follicular phase) causes
Proliferation of stromal cells
Proliferation of epithelial cells
Re-epithelialization in 4-7 days after beginning of menstruation
Growth of glands and blood vessels
Great increase in the thickness of endometrium
Cervical gland (other endometrial glands as well) produce strings of mucus
Thickness of endometrium reaches 3-5 mm till the time of ovulation

28. Secretory phase Occurs after ovulation
Corpus luteum secretes both estrogen and progesterone
Estrogen continues the proliferative changes
Progesterone brings about additional changes in the endometrium

29. Variations in the female hormones

30. Secretory phase Progesterone causes
Marked swelling and secretory development
Glands grow more and become tortuous
Appearance of secretory substances in the glandular cells
Deposition of lipids and glycogen in the stromal cells
Further growth and tortuosity of the blood vessels
Thickness of endometrium 6-8 mm

31. The Endometrial Cycle

32. Secretory phase Endometrium is now well prepared for implantation
Endometrial gland secrete “Uterine milk” for nutrition of fertilized ovum even before implantation
Entry of ovum 3-4 days after ovulation
Implantation 7-9 days after ovulation
Endometrium contain large amount of nutrients for implanted fertilized ovum
Trophoblastic cells at the implantation sites can digest and absorb the stromal cells nutrients for the embryo

33. The Endometrial Cycle
Figure 28.20

34. Menstrual phase If fertilization does not occur
Corpus luteum involutes on 12th day of ovulation
Absence of estrogen and progesterone
Necrotic changes in the endometrium
Shedding of endometrium
Menstrual flow

35. Menstrual phase Absence of progesterone (& estrogen)
↓stimulation of endometrium →regression of thickness to 65%
Vasospasm of the endometrial blood vessels
Due to prostaglandins or other vasoconstrictors
Vasospasm → ↓nutrition
Necrosis of blood vessels
Seepage of blood in many areas
Growth of hemorrhagic areas
Necrotic outer layers separated from basal layers

36. Menstrual phase Menstrual flow starts
Within 48 hours all the endometrium is desquamated
The necrotic tissue in the uterine cavity
Onset of uterine contraction by prostaglandins
Expulsion of contents
About 40 ml blood loss
About 35 ml serous fluid loss
Fibrinolysin in the necrotic tissue in the menstrual blood prevent clotting
Excessive bleeding may cause passage of clots
Clots usually sign of pathology
After 4-7 days new cycle of proliferation starts

37. The Uterine Wall

38. Leucorrhea during menstruation
Chemotactic substances in the necrotic tissue
Large number of WBCs passed in the menstrual blood
Uterus is resistant to infections in spite of denuded, desquamated surface of endometrium

39. Thank-you
Questions ??