Module A

Female Genital System

Martin Špaček Histology and

• Pictures from: • Junqueira et al.: Basic histology • Rarey, Romrell: Clinical human embryology • Sadler: Langman’s medical embryology • Young, Heath: Wheather’s functional histology • http://www.med.unc.edu/embryo_images Genital System Development

• Development of the indifferent stages – see presentation “Male genital system”

http://www.lf3.cuni.cz/histologie Development of the Ovary • Absence of TDF (testis-determining factor) • Primitive degenerate Development of the Ovary • Surface epithelium gives rise to a second generation of cords – cortical cords • Epithelial cells surrounding the germ cells form the follicular cells Development of the Genital Ducts

• Absence of MIS (Müllerian inhibiting substance) in the female • Regression of the mesonephric (Wolffian) ducts Development of the Genital Ducts • Paramesonephric (Müllerian) ducts: – cranial ends → uterine tubes – caudal segments → uterus, upper part of the Development of the Genital Ducts • Vagina develops from: – caudal segments of the paramesonephric ducts – vaginal plate Development of the Genital Ducts • Abnormalities of the uterus and vagina – lack of fusion of the paramesonephric ducts – or the atresia Development of the Genital Ducts • Remnants of the mesonephric tubules and ducts – epoophron, paroophron, Gartner’s canal External Genitalia in the Female • indiferent stage • female genital – absence of testosterone • • clitoris • urogenital folds • labia minora • genital swellings • labia majora Female Pseudohermaphroditism ƒ Adrenogenital syndrome ƒ masculinization of the external genitalia caused by excessive production of by the adrenals ƒ 46, XX: Histology of the Female Genital System

•Ovary • Uterine tube • Uterus (Womb) •Vagina • External genitalia Ovary

ƒ Cortical region ƒ simple squamous or cuboidal epithelium (germinal epithelium) ƒ tunica albuginea ƒ loose connective tissue, fibroblasts ƒ ovarian follicles ƒ Medullary region ƒ loose connective tissue, vessels Ovarian Follicles Primordial Follicles

ƒ Oocyte ƒ spherical cell with large nucleus ƒ Single layer of flattened follicular cells Primary Follicles ƒ Follicular cells ƒ cuboidal, ƒ single → stratified epithelium = granulosa layer ƒ Zona pellucida ƒ surrounds oocyte (glycoproteins) ƒ Theca folliculi ƒ differentiating stroma around the follicle Secondary (vesicular) Follicle

ƒ Cavities between the cells → antrum ƒ Theca differentiates into two layers: ƒ theca interna – produce androstendion ƒ theca externa

Mature Follicle (Graafian) ƒ Measures about 2 cm in diameter ƒ Cumulus oophorus ƒ cluster of follicular cells between the oocyte and the wall of the follicle ƒ Corona radiata ƒ single layer of follicular cells around the oocyte

Ovulation

ƒ Rupture of the mature follicle ƒ Oocyte with the zona pellucida and the corona radiata is released ƒ Oocyte enters the uterine tube Slide G1 – Ovary HE Slide G1 – Ovary HE Slide G1 – Ovary HE SlideSlide G3G3 –– OvaryOvary (rabbit)(rabbit) HEHE Corpus Luteum

ƒ After ovulation the granulosa cells and the theca interna transform into a corpus luteum ƒ Corpus luteum of menstruation (lasts 14 days) ƒ Corpus luteum of pregnancy (stimulated by hCG) ƒ Corpus albicans Corpus Luteum ƒ Invasion of blood vessels, connective tissue ƒ Granulosa lutein cells and theca lutein cells ƒ produce progesteron and estrogens SlideSlide G2G2 –– CorpusCorpus LuteumLuteum HEHE SlideSlide G2G2 –– CorpusCorpus LuteumLuteum HEHE Oviducts (Fallopian or Uterine Tube) ƒ Mucosa ƒ mucosal folds ƒ simple columnar epithelium – ciliated and secretory cells ƒ lamina propria ƒ Muscular layer ƒ inner circular ƒ outer longitudinal ƒ Serosa layer ƒ = visceral peritoneum

SlideSlide G4G4 –– uterineuterine tubetube ((isthmusisthmus)) SlideSlide G5G5 –– uterineuterine tubetube ((ampullaampulla)) SlideSlide G5G5 –– uterineuterine tubetube ((ampullaampulla)) SlideSlide G5G5 –– uterineuterine tubetube ((ampullaampulla)) Uterus ƒ Endometrium (mucosa) ƒ simple columnar epithelium with ciliated and secretory cells ƒ lamina propria – simple tubular glands ƒ functionally basal layer and functional layer ƒ Myometrium ƒ thick smooth muscle layer ƒ Adventitia or serosa Menstrual Cycle ƒ The menstrual phase (the 1st to the 4th day) ƒ The proliferative phase (the 5th to the 14th day) ƒ Secretory (luteal) phase (the 15th to the 28th day) Menstrual Phase

ƒ Corpus luteum ceases function → drop of the levels of progesterone and estrogens ƒ Ischemia ƒ Necrosis of the functionalis layer ƒ Bleeding Proliferative Phase

ƒ Estrogenic or follicular phase ƒ Proliferation of the cells ƒ Glands straight and narrow Secretory Phase ƒ Depends on the progesterone secreted by the corpus luteum ƒ Endometrial glands initiate their secretory activity ƒ Glands become highly coiled SlideSlide G6G6 –– fundusfundus uteriuteri HEHE SlideSlide G6G6 –– fundusfundus uteriuteri HEHE Uterine Cervix

ƒ Endocervix ƒ simple columnar epithelium ƒ cervical glands (may become obstructed → nabothian cysts) ƒ Ectocervix ƒ external segment that bulges into the vagina ƒ stratified squamous epithelium Uterine Cervix

ƒ Transformation zone ƒ abrupt epithelial transition between the endocervix and the ectocervix ƒ dysplasia, carcinoma in situ, invasive carcinoma Papanicolaou Smear

• Cytologic analysis of smears of the cervical epithelium • Can detect dysplasia and carcinoma in situ SlideSlide G7G7 –– cervixcervix uteriuteri HEHE Vagina

• Mucosa layer – stratified squamous epithelium • accumulate glycogen (→ lactic acide) – lamina propria (devoid of glands) • Muscular layer – mainly longitudinal smooth muscle • Adventitial layer – dense connective tissue, rich in elastic fibers SlideSlide G9G9 –– VVaginaagina ((PASPAS++HH)) SlideSlide G9G9 –– VVaginaagina ((PASPAS++HH)) SlideSlide G10G10 –– VVaginaagina HEHE SlideSlide G10G10 –– VVaginaagina HEHE External Genitalia

• Modified skin structures – (keratinized) stratified squamous epithelium •Monspubis • Labia majora – adipose tissue, hair – apocrine sweat glands and sebaceous glands • Labia minora – skin folds without adipose tissue • Clitoris – two erectile bodies