Placenta and the Male Reproductive System

1. Placenta and the Male Reproductive System Rachel Boggus Boggusrl@email.uc.edu

2. Orientation to development of the placenta • What happens to the stratum functionalis after implantation? • What are these responses called? What is the endometrium now called? Free template from www.brainybetty.com

3. Orientation to development of the placenta • What happens to the stratum functionalis after implantation? • Cells enlarge and proliferate decidual cells… synthesize prolactin and relaxin. Also becomes more highly vascularized • What are these responses called? What is the endometrium now called? • Called decidual reaction, endometrium called decidua Free template from www.brainybetty.com

4. decidual cells relaxin prolactin Free template from www.brainybetty.com

5. Selective elaboration of the chorion • What does it mean to say that implantation is interstitial? • What is the chorion frondosum? • What is the chorion laeve? Free template from www.brainybetty.com

6. Selective elaboration of the chorion • What does it mean to say that implantation is interstitial? • Embryo completely embeds itself into maternal decidual tissue • What is the chorion frondosum? • Disk shaped region of chorion that continues to develop • What is the chorion laeve? • Regions of chorion near decidua capsularis that regress Free template from www.brainybetty.com

7. Elaboration of the Amniotic Cavity • Just remember that it keeps getting bigger and eventually the two layers of intraembryonic mesoderm fuse together Free template from www.brainybetty.com

8. Development of Embryonic Circulation • Develops from intraembryonic mesenchyme within the fetus • These vessels are connected to two umbilical arteries and one umbilical vein. Free template from www.brainybetty.com

9. What are the layers of the early placenta? Free template from www.brainybetty.com

10. What are the layers of the early placenta? • Epithelial layer of the amnion • Extraembryonic mesenchyme • Cytotrophoblast • Syncytiotrophoblast • Zone connecting villi and lacunae (intervillous space) • Syncytiotrophoblast • Maternal decidua Free template from www.brainybetty.com

11. Placenta • What is the chorionic plate? Free template from www.brainybetty.com

12. Placenta • What is the chorionic plate? • Syncytiotrophoblast, cytotrophoblast and underlying extraembryonic reticulum Free template from www.brainybetty.com

13. Histology • What are hofbauer cells? • Where are they visualized? • What are anchoring villi? • What is the cytotrophoblastic shell? Free template from www.brainybetty.com

14. Histology • What are hofbauer cells? • Fetal macrophages • Where are they visualized? • Within mesenchyme of the villi • What are anchoring villi? • Stem villi that extend across the intervillous space and connect with the decidual side Free template from www.brainybetty.com

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17. Red = chorionic plate; blue = stem villi • If it reaches the other side it is an anchoring villi Free template from www.brainybetty.com

18. Green arrows: anchoring villi; cytotrophoblasts: blue arrowRed Arrow: fibrinoid Free template from www.brainybetty.com

19. Placenta • What is the maternal side of the placenta called? What is it composed of? • What is fibrinoid? Free template from www.brainybetty.com

20. Placenta • What is the maternal side of the placenta called? What is it composed of? • Basal plate, syncytiotrophoblast, cytotrophoblast shell, and decidual tissue • What is fibrinoid? • Extravillous cytotrophoblast cells and maternal blood clots form this acidophilic extracellular matrix Free template from www.brainybetty.com

21. Basal plate between arrows Free template from www.brainybetty.com

22. Functions of syncytiotrophoblast • What are cytotrophoblast cells like? • What about the syncytiotrophoblasts? (hormones, appearance?) • What maintains the corpus luteum? Free template from www.brainybetty.com

23. Functions of syncytiotrophoblast • What are cytotrophoblast cells like? • Stem cells—cuboidal, dispersed chromatin, lack of elaborate organelles • What about the syncytiotrophoblasts? (hormones, appearance?) • Very active cells—multinucleated, microvilli, numerous pinocytic vesicles. HCG, estrogen, progesterone and prolactin • What maintains the corpus luteum? • HCG Free template from www.brainybetty.com

24. Red Arrow: cytotrophoblastBlue Arrows: Syncytiotrophoblast Free template from www.brainybetty.com

25. Maternal cotyledons • What are they? Free template from www.brainybetty.com

26. Maternal cotyledons • What are they? • Formed by placental septa • Composed of core of decidual tissue covered by cytotrophoblast and snycytiotrophoblast. • Do not reach the opposing chorionic plate Free template from www.brainybetty.com

27. Gas Exchange • They love to ask questions about gas exchange so know this! • Is there direct mixing of fetal and maternal blood? • What are the layers that O2 must pass through initially? Free template from www.brainybetty.com

28. Gas Exchange • They love to ask questions about gas exchange so know this! • Is there direct mixing of fetal and maternal blood? NO • What are the layers that O2 must pass through initially? • syncytiotrophoblast • cytotrophoblast • basement membrane cytotropho.. • extraembryonic mesenchyme • basement memb. Fetal endoth. • fetal endothelial cells Free template from www.brainybetty.com

29. What are the modifications as the placental matures? • Clustering of the nuclei of syncytiotrophoblast syncytial knots • Cytotrophoblast cells cease division (eventually not a continuous layer) • Fetal bld vessels move closer to syncytiotrophoblast layer (eventually basal lamina of syncyts. Fuses with fetal endothelium basal lamina.) Free template from www.brainybetty.com

30. Syncytial knots (they LOVE these) Free template from www.brainybetty.com

31. Umbilical cord • What does the core develop from? • What does the mesenchyme form? • What covers the outside of the cord? • What does the mature umbilical cord consist of? Free template from www.brainybetty.com

32. Umbilical cord • What does the core develop from? • Extraembryonic mesenchyme of connecting stalk • What else does it form? • Umbilical vessels • What covers the outside of the cord? • The expanding amniotic membrane • What does the mature umbilical cord consist of? • Outer epithelial covering (amniotic memb.), inner mucus CT (wharton’s jelly), and umbilical vessels Free template from www.brainybetty.com

33. Two arteries, one vein Free template from www.brainybetty.com

34. Mammary Gland • How many lactiferous ducts are in each breast? • Remember that they each emerge as a separate opening • What happens just under the epithelium? • What happens to the epithelium? Free template from www.brainybetty.com

35. Mammary Gland • How many lactiferous ducts are in each breast? 15-25 • Remember that they each emerge as a separate opening • What happens just under the epithelium? • They dilate to form lactiferous sinus • What happens to the epithelium? • Strat squam at openingstrat columnarstrat, cuboidalsimple cuboidal with myoepithelial cells Free template from www.brainybetty.com

36. Alveolar system • What are the milk components, how are they produced? Free template from www.brainybetty.com

37. Alveolar system • What are the milk components, how are they produced? • Milk proteins synthesized by RER and secreted by exocytosis • Lipid droplets not membrane bound and are released within plasma memb. TRUE apocrine secretion • IgA moved by transcytosissIgA Free template from www.brainybetty.com

38. Lobes, lobules, and CT • Remember that each lactiferous duct drains one lobe • Lobes divided into lobules • Within each lobule, intralobular CT is loose with lots of plasma cells which make the IgA • Between lobules, interlobular CT is dense and less cellular • Lots of adipose tissue surrounds the lobes Free template from www.brainybetty.com

39. Nipple and areola • What is the epithelium? • How is it different than the rest of the breast? Free template from www.brainybetty.com

40. Nipple and areola • What is the epithelium? • Stratified squamous epithelium • How is it different than the rest of the breast? • Longer dermal papilla Free template from www.brainybetty.com

41. Nipple; blue = smooth muscle; note large dermal papilla Free template from www.brainybetty.com

42. Mammary Gland Development • Before puberty sparse duct system with little adipose tissue • At puberty which hormones induce secondary sex characteristics in breasts? • What are these changes? Free template from www.brainybetty.com

43. Mammary Gland Development • Before puberty sparse duct system with little adipose tissue • At puberty which hormones induce secondary sex characteristics in breasts? • Estrogen, progesterone, growth hormone, thyroid hormone, glucocorticoids • What are these changes? • Inc. adipose, CT, and bld. Vessels, enlargement of areola Free template from www.brainybetty.com

44. Post-puberty • Cyclical changes in response to hormones • Beginning of cycle—sparse glands and ducts. End—more elaborate and lumen apparent within alveoli • Pregnancy—estrogen induces branching and progesterone cause alveolar development • Towards the end of pregnancy secretory cells enlarge and distend with colostrum • Expansion of the duct is at the expense of the surrounding fat and CT. • After birth produces milk rich in lipid • SECRETORY cells eosinophilic with clear vacuoles from lipid droplet dissolution Free template from www.brainybetty.com

45. Immature breast Free template from www.brainybetty.com

46. Inactive mammary gland Free template from www.brainybetty.com

47. Active Mammary gland Free template from www.brainybetty.com

48. Lactating mammary gland – fat droplets IN CELLS Free template from www.brainybetty.com

49. Regressing mammary gland Free template from www.brainybetty.com

50. Hormones and milk production • What happens to prolactin levels throughout pregnancy? • What happens to estrogen and progesterone at birth? • What happens with suckling? Free template from www.brainybetty.com