Physiology department1 Physiology of reproduction. 2 Hypothalamus – hypophysis – gonads 3 Hypothalamus – hypophysis – gonads 4 Hypothalamus – hypophysis – gonads 5 Hypothalamus – hypophysis – gonads 6 Menstrual cycle follicle selection ovulation corpus luteum 37◦ 36◦ LH FSH E P menstruation1 14 28 1follicular phase luteal phase 7 Negative feedback HYPOTHALAMUS GnRH LH LH FSH FSH INHIBIN HYPOFYSIS PROGESTINS ESTROGENS ANDROGENS 8 Positive feedback HYPOTHALAMUS GnRH LH LH FSH FSH HYPOFYSIS ESTROGENS ANDROGENS 9 Ovarian cycle corpus haemorraghicum dominant follicle primary follicle ovum corpus luteum corpus albicans primordial follicles 10 Menstrual cycle follicle selection ovulation corpus luteum 37◦ 36◦ LH FSH E P proliferative phase secretory phase menstruation1 14 28 1 menstruation 11 Contraceptives BARRIER CONTRACEPTIVES: • condoms • contraceptive sponges with spermicide • diaphragms • cervical caps HORMONAL: • oral pills • implants under the skin • injections • patches • IUDs • vaginal ring INTRAUTERINE DEVICES: • copper IUDs • IUD with levonorgestrel STERILIZATION: • tubal ligation • vasektomy BEHAVIORAL: • fertility awareness methods • coitus interruptus • lactation 12 Oral pills 0,4 0 0,1 0,2 0,3 1 7 14 21 28 day P E 13 Oral pills ̶ Progestational effects include: ̶ Inhibition of ovulation by suppressing luteinizing hormone (LH); ̶ Thickening of cervical mucus, thus hampering the transport of sperm; ̶ Possible inhibition of sperm capacitation; ̶ Hampered implantation by the production of decidualized endometrium with exhausted and atrophic glands ̶ Estrogenic effects include: ̶ Partial inhibition of ovulation in part by the suppression of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), depending on dose; ̶ Alteration of secretions and cellular structures of the endometrium within the uterus 14 Benefits and riscs of HC reducing the risk of total cancer by 12%: ― ovarian cancer ― endometrial cancer ― colorectal cancer ― ovarian cysts acne ― venous thromboembolism (VTE) ― arterial thrombosis (AT) ― breast cancer ― diseases associated with VTE and AT 15 Functions of the PLACENTA ̶ TRANSPOR function ̶ Respiratory gases ̶ transport and metabolism of sacharides ̶ transport and metabolism of aminoacods ̶ transport and metabolism of fat ̶ transport of H2O, minerals and vitamines ̶ ENDOCRIN function ̶ Estrogens ̶ Progesteron ̶ HCG ̶ HPL ̶ Growth factors (epidermal and insulin-like growth factors) ̶ PROTECTIV function ̶ Cytochrom P450 ̶ Pinocytosis (IgG) ̶ Barier against bacterias, virus etc. 16 HCG 1 2 3 4 8 12 16 20 24 28 32 36 40 HCG (Human Chorionic Gonadotropin) ― Glycoprotein ― secreted by the syncytial trophoblast cells ― prevents involution of the corpus luteum ― prevent menstruation and cause the endometrium to continue to grow ― can first be measured in the blood 8 to 9 days after implantation ― effect on the fetal testes ― ↓ - ectopic pregnancy, dead fetus ― ↑ - multiple pregnancy and diagnosis of trisomy 21 - Down syndrome 17 HCG 18 RX 1 2 3 4 8 12 16 20 24 28 32 36 40 RX RX (Relaxin) ― relaxes the pubic symphysis and other pelvic joints and softens ― dilates the uterine cervix ― mediate hemodynamic changes (pregnancy) 19 RX 20 HCS/HPL HCS/HPL 1 2 3 4 8 12 16 20 24 28 32 36 40 HCS (Human Chorionic Somatomammotropin) placental growth hormone - Human placental lactogen (hPL) ― has weak actions similar of growth hormone ― causes retention of nitrogen, potassium, calcium ― causes decreased insulin sensitivity and decreased utilization of glucose in the mother ― secretion of this hormone increases progressively in direct proportion to the weight of the placenta 21 PROL 1 2 3 4 8 12 16 20 24 28 32 36 40 PROL PROL (Prolactin) luteotropic hormone or luteotropin ― stimulates the mammary glands to produce milk (lactation) ― provides the body with sexual gratification after sexual acts ― plays an important role in maternal behavior ― inhibits maturation of ovum 22 OX 1 2 3 4 8 12 16 20 24 28 32 36 40 OX OX (Oxytocin) ― secreted by the neurohypophysis (nucleus paraventricularis) ― causes uterine contraction ― mediates the let-down reflex 23 OX 24 Progesteron P 1 2 3 4 8 12 16 20 24 28 32 36 40 P (Progesteron) ― causes decidual cells to develop in the uterine endometrium ― decreases the contractility of the pregnant uterus ― contributes to the development of the conceptus even before implantation ― prepares the mother’s breasts for lactation 25 Estroen E 1 2 3 4 8 12 16 20 24 28 32 36 40 E (Estrogen) ― enlargement of the mother’s uterus ― enlargement of the mother’s breasts and growth of the breast ductal structure ― and enlargement of the mother’s female external genitalia ― relax the pelvic ligaments of the mother ― dampen the formation of the pituitary gonadotropins - not mature further follicles, miss menstrual cycles 26 HCG P E HPL 1 2 3 4 8 12 16 20 24 28 32 36 40 PROL OX RX 27 Fetoplacental unit FETUS HPA axis CORTISOL PLACENTAL ENDOCRINE AXIS UTERINE GROWTH ACTIVATION STIMULATION EXTENSION OF UTERUS P E (+) (-) • oxytocin • PGs • Gap junctions PARTURITION GROWTH OF FETUS 28 FETOPLACENTAL UNIT MATERNAL COMPARTMENT hypotalamus neurohypophysis oxytocin cortisol FETUS cortisol hypotalamus adenohypophysis ardenal glands cortisol CRH ACTH (preparation of fetal organs) cortisol uterus PGs placental OT estrogens cholesterol placental CRH (vazodilation of the placenta) PARTURITION Fetoplacental unit 29 Lactation 30 Physiological changes during pregnancy 31 THANK YOU FOR YOUR ATENTION