Ovary Primordial Follicle

Histology Practical

8th of October 2008

Slide #:

63 Ovary

Ovary—Primordial Follicle The ovary consists of an outer cortex 1 and an inner medulla (zona vasculosa) 2 . The medulla contains connective tissue, muscle cells, elastic and reticular fibers and vessels. Follicles are not present. This figure shows the cortex of a feline ovary. It consists of the surface epithelium (also called germinal epithelium) 3 , the tunica albuginea 4 and the cortical stroma 1 . The surface epithelium is single-layered, and its cells are cuboidal or columnar. At the mesovarium, it becomes continuous with the squamous peritoneal epithelium. The layer of cells and fibers of the tunica albuginea 4 underneath the surface epithelium does not contain follicles. This layer is followed by the cortical stroma (zona parenchymatosa). It consists of connective tissue cells, myofibroblasts and interstitial gland cells and contains primordial follicles and primary follicles. 1 Cortical stroma with many primordial and primary follicles 2 Ovarian medulla (zona vasculosa) 3 Surface epithelium 4 Tunica albuginea Semi-thin section; stain: methylene blue-azure II; magnification: × 200

Ovary—Secondary Follicle or Preantral Follicle Secondary follicle or preantral follicle fromthe ovary of a 30-year-oldwoman. The follicular epithelium 1 is now multilayered (granulosa epithelium, stratum granulosum). Secondary follicles can become up to 400μm thick. Note the zona pellucida 2 between oocyte plasma

Copyright by Matthias Heyner Based on the Histology practical from E. Dobo et. al at the University of Szeged membrane and granulosa epithelium aswell as the basal membrane 3 between granulosa epithelium and the theca folliculi (the connective tissue sheath of the cortical stroma). The ovarian cytoplasm is sparsely granulated. The large nucleus contains a prominent nucleolus. 1 Follicular epithelium 2 Zona pellucida 3 Basal membrane 4 Theca folliculi Stain: hematoxylin-eosin; magnification: × 300

Ovary—Primary Follicle—Secondary Follicle Partial section of the cortical stroma from a feline ovary with ovarian follicles in different stages of development and decline. a) and b) Primary follicle. The cells of the single-layered epithelium of the follicle are cuboidal or columnar. A basement membrane (zona pellucida) is interleaved between the oocyte plasma membrane and the follicular epithelium. A basal membrane and a connective tissue sheath (theca folliculi) encase the primary follicle. The connective tissue of the theca folliculi is poorly developed at this developmental stage. c) A multilayered epithelium is formed in the course of the maturation of the follicle: Secondary follicle (preantral follicle). The surface epithelium (follicular epithelium, stratum granulosum) is also called granular epithelium. The zona pellucid is well defined as a homogeneous glycoprotein layer. The connective tissue sheath (theca folliculi) follows it. The sheath shows a concentric arrangement of cells. d) Atresia of a secondary follicle. The follicle shows remnants of the follicular epithelium. The oocyte is completely resorbed. The folded reddish band is the now hyaline zona pellucida. a) and b) stain: alum hematoxylin-eosin; c) and d) alum hematoxylin-chromotrope 2R (acid red 29); magnification (all): × 240 Pictures and text used from Kuehnel, Color Atlas of Cytology, Histology, and Microscopic Anatomy © 2003 Thieme

Ovary  Simple Cuboidal epithelium  Corpus luteum (oestrogen producing) – released by hypophysis  Fibroblasts in the stroma – spindle shaped  Primordial follicle  Unilaminar primary follicle  Multilaminar primary follicle  At retic follicles (derive from primary or secondary follicles) + hyaline structure  Secondary follicle – steroid producing (granulosal cells + basal membrane) Ovary Mature follicle  Theca follicle interna From o Membrana granulose Outer o Cavum folliculi Layer Towards Inside o Corona radiate -cuniculus oophorus o Zona pellucid -cuniculus oophorus o Oocyte -cuniculus oophorus  Medulla

The wall structure of the uterine tube: 64 Oviduct / Uterine Tube  Tunica serosa  Tunica Subserosa  Tunicae Muscularis

Copyright by Matthias Heyner Based on the Histology practical from E. Dobo et. al at the University of Szeged  Mucosal folds Oviduct—Ampulla Tubae Uterinae The human oviduct (tuba uterina, Fallopian tube) is about 10–15cm long. It consists of tunica mucosa, tunica muscularis, the vascularized tela subserosa and the tunicaserosa. All layers are shown in this section. The mucosa of the ampulla of the Fallopian tube rises to high longitudinal folds 1 . The folds subdivide into elaborately branched secondary and tertiary folds . This considerably reduces the lumen of the oviduct. The tunica muscularis (tuba uterinae musculature) consists of three layers. These layers are helical and show very irregular configurations. The inner and outer layers are longitudinal muscle bundles, and the muscle bundles in the middle layer have a circular structure. The wide subserosal tissue layer contains numerous vessels 3 4 . There are also cords of smooth muscle cells of variable density in the subperitoneal muscle layer, which connects with the uterus, the mesosalpinx 5 and the mesovarium. The muscles enable changes in the positioning of the oviduct. The single-layered peritoneal epithelium is very shiny and flat. The tunica serosa 6 covers the subserosal tissue. 1 Mucosa fold (plica) 2 Oviduct musculature 3 Artery 4 Vein 5 Mesosalpinx 6 Tunica serosa Stain: iron hematoxylin-eosin; magnification: × 10