Oral Contraceptives Estrogen and Progestin What we will

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_view 0/chapter 47/animations. html# 3

Interaction of Hormones with Surface Proteins 4

Ovulation • Follicular phase – LH and FSH concentrations increase due to Gn. RH – 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 1 st progestin • 1960 - FDA approves “the pill” • 1963 - 1 st 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 (Gn. RH) • Synthesized by hypothalamus • Stimulates anterior pituitary gland to release FSH and LH • A decapetide (contains 10 amino acids) p. Glu-His-Tyr-Gly-Leu-Arg-Pro-Gly. NH 2 • 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→Gn. RH→ Pituitary→FSH→Follicle→Estrogens 12

Naturally occurring estrogens Estradiol 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 Action 1) 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→Gn. RH→ 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) C 19 - derived from testosterone 2) C 21 - 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 Modi. Co 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/a 601 050. html http: //en. wikipedia. org/wiki/Estrogen http: //users. rcn. com/jkimball. ma. ultranet/Biology. Pages/S/Sex Hormones. html http: //www. emc. maricopa. edu/faculty/farabee/biobk/Bio. Book REPROD. html http: //en. wikipedia. org/wiki/Gonadotropin_releasing_hormone http: //www. contraceptiononline. org/slides/slide 01. cfm? q=prog estin+chemical+structures&dpg=1 http: //users. rcn. com/jkimball. ma. ultranet/Biology. Pages/H/Hor mones. html http: //www. contraceptiononline. org/contrareport/article 01. cfm ? art=93 http: //users. rcn. com/jkimball. ma. ultranet/Biology. Pages/G/G_ Proteins. html 24

Thank you 25