Transcript Oral Contraceptives

Oral Contraceptives
Estrogen and Progestin
What we will be
talking about today
•
•
•
•
•
•
•
Hormones
Ovulation
History of Oral Contraceptives
Uses of Oral Contraceptives
Estrogen and Progestin
Types of Oral Contraceptives
Future of Oral Contraceptives
2
Hormones
= “chemical messenger from one cell to another”
4 classes of Hormones
•
Amine Derived Hormones
•
Peptide Hormones
•
Steroid Hormones
•
Lipid and Phospholipid Hormones
Steroid Hormones
-derived from cholesterol
-primarily produced in adrenal cortex or gonads
Types of Steroid Hormones
•
Anabolic steroids
•
Corticosteroids
•
Sex hormones
cholesterol
Major steps in Steroid Hormone Binding
•
http://highered.mcgrawhill.com/sites/0072437316/student_view0/chapter47/animations.html#
3
Interaction of Hormones with
Surface Proteins
4
Ovulation
• Follicular phase
– LH and FSH
concentrations increase
due to GnRH
– Follicular growth
– Antrum fluid volume
increases
– Blister forms in ovary
• Ovulation Phase
– Follicle released from
ovary  secretes estrogen
– Corpus lueteum triggers
release of progesterones
and estrogens
5
Ovulation
6
History of Oral
Contraceptives
• 1937- discovery of effects of progesterone on
ovulation
• 1940’s- Russell Marker isolates progesterone
from Mexican yams
• 1951- Luis Miramontes synthesizes 1st
progestin
• 1960- FDA approves “the pill”
• 1963- 1st oral contraceptive put on drug
market
• 1965- number one form of birth control
• Late 1970’s- FDA mandated warning that
indicated oral contraceptives carried risks of
cancer and blood clots
7
Uses of Oral Contraceptives
• Primary Use
– Prevent pregnancy
• Secondary Uses
– Heavy or irregular menstruation
– Endometriosis
– polycystic ovary syndrome
– dysfunctional uterine bleeding
8
What’s in “The Pill”
• 20-40 micrograms ethinyl estradiol (synthetic
form of estrogen)
• Varying amounts of either levonorgestrel or
norethindrone as the progestagen component
• Types of Regimens
– 21-day or 28-day pack
9
Combined mode of action of
estrogen and progestin
•
•
•
Prevents ovulation
Thickens mucous in cervix
Thins endometrium
10
Gonadotropin Releasing
Hormone (GnRH)
• Synthesized by hypothalamus
• Stimulates anterior pituitary gland
to release FSH and LH
• A decapetide (contains 10 amino
acids)
pGlu-His-Tyr-Gly-Leu-Arg-Pro-GlyNH2
• secretion begins at puberty
• Primary Effects
– secretion of estrogen
and progesterone in
females
– secretion of testosterone
in males
11
Estrogen
• Primary female sex hormone
• Roles of estrogen:
– To develop secondary female sex
characteristics
– Thicken the endometrium
– Regulate menstrual cycle
• Regulation
– Production of estrogen regulated by
Follicle Stimulating hormone (FSH) and
Luetinizing hormone (LH), both produced
in the anterior lobe of the pituitary gland
• Hypothalamus→GnRH→
Pituitary→FSH→Follicle→Estrogens
12
Naturally occurring estrogens
Estradiol
Estriol
Estrone
13
Conversion of testosterone to
estradiol
Testosterone
Estradiol
14
Synthetic Estrogens
15
Estrogen Receptors
Two types of Receptors
• ER alpha
• ER beta
Mode of Action1) Estrogen passes through
phospholipid bilayer
2) Ligand binds in hydrophobic
region of receptor forming cap
over ligand binding pocket
3) Estrogen and ER complex
bind to estrogen response
element in the nucleus to
initiate transcription
4) Translation creates proteins
which target various organs
and processes in the female
body
16
Progesterone
•
Produced by
– Adrenal glands
– Gonads
– Brain
– Placenta (only during pregnancy)
•
Regulation- stimulated by the production of LH
•
Hypothalamus→GnRH→ Pituitary→LH→Corpus luteum→Progesterone
•
Primary Effect- prepares uterus for implantation by the proliferation of
endometrium; prepares body for pregnancy
•
Natural progesterone- destroys digestive system when consumed orally
ALL oral contraceptives contain progestin,
synthetic form of progesterone
17
Conversion of pregnenolone
to progesterone
pregnenolone
progesterone
18
Progestins
• Types
1) C19- derived from testosterone
2) C21- derived from progesterone
• Role
– in adequate doses it inhibits ovulation
– Makes your body think that it is pregnant
– Reduces levels of FSH and LH
• Binding
– Interacts with progesterone receptors either
by entering cells through phospholipid bilayer
or by interacting with surface proteins
19
Structure of Progestins
20
Brands of Oral Contraceptives
•
•
•
•
•
•
•
•
•
•
•
•
Alesse
Brevicon
Cyclessa
Demulen
Desogen
Estrostep
Genora
Intercon
Jenest
Levlen
Levlite
Levora
•
•
•
•
•
•
•
•
•
•
•
•
Loestrin
Lo/Ovral
Mircette
ModiCo
Necon
N.E.E.
Nelova
Nordette
Norethin
Norinyl
Ortho-Cept
Ortho-Cyclen
•
•
•
•
•
•
•
•
•
Ortho-Novum
Ortho Tri-Cyclen
Ovcon
Ovral
Tri-Levlen
Tri-Noriny
Triphasil
Trivora
Zovia
21
Side Effects of Oral
Contraceptives
• Changes in:
–
–
–
–
–
–
–
Weight
Sexual desire
Vaginal discharge
Menstrual flow
Breast size
Blood pressure
complexion
• Other Common side effects:
–
–
–
–
–
Breakthrough bleeding
Nausea headaches
Urinary tract infection
Depression
Gum inflammation
22
Future of Oral Contraceptives
• Researchers continually trying to minimize
adverse side effects of oral contraceptives
• Pharmaceutical companies have to compete
with latest forms of contraception
–
–
–
–
–
–
Contraceptive vaccines
Vaginal rings
Intrauterine Contraception
Cervical caps
Transdermal patch
Implants and injectables
23
References
•
•
•
•
•
•
•
•
•
http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a601
050.html
http://en.wikipedia.org/wiki/Estrogen
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/S/Sex
Hormones.html
http://www.emc.maricopa.edu/faculty/farabee/biobk/BioBookR
EPROD.html
http://en.wikipedia.org/wiki/Gonadotropin_releasing_hormone
http://www.contraceptiononline.org/slides/slide01.cfm?q=prog
estin+chemical+structures&dpg=1
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/H/Hor
mones.html
http://www.contraceptiononline.org/contrareport/article01.cfm
?art=93
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/G/G_
Proteins.html
24
Thank you
25