Endometrium - Histology


The endometrium consists of a single layer of columnar epithelium resting on the stroma, a layer of connective tissue that varies in thickness according to hormonal influences. Simple tubular uterine glands reach from the endometrial surface through to the base of the stroma, which also carries a rich blood supply of spiral arteries. In a woman of reproductive age, two layers of endometrium can be distinguished. These two layers occur only in endometrium lining the cavity of the uterus, not in the lining of the Fallopian tubes:

  • The functional layer is adjacent to the uterine cavity. This layer is built up after the end of menstruation during the first part of the previous menstrual cycle. Proliferation is induced by estrogen (follicular phase of menstrual cycle), and later changes in this layer are engendered by progestrone from the corpus luteum (luteal phase). It is adapted to provide an optimum environment for the implantation and growth of the embryo. This layer is completely shed during menstruation.
  • The basal layer, adjacent to the myometrium and below the functional layer, is not shed at any time during the menstrual cycle, and from it the functional layer develops.

In the absence of progesterone, the arteries supplying blood to the functional layer constrict, so that cells in that layer become ischaemic and die, leading to menstruation.

It is possible to identify the phase of the menstrual cycle by observing histological differences at each phase:

Phase Days Thickness Epithelium
menstrual phase 1-4 thin absent
proliferative phase 4-14 intermediate columnar
secretory phase 15-28 thick columnar. Also visible are helicine branches of uterine artery

Chorionic tissue can result in marked endometrial changes, known as an Arias-Stella reaction, that have an appearance similar to cancer. Historically, this change was diagnosed as endometrial cancer and it is important only in so far as it should not be misdiagnosed as cancer.

Read more about this topic:  Endometrium

Other articles related to "histology":

Atypical Teratoid Rhabdoid Tumor - Pathology - Histology
... Histology is the study of the microscopic anatomy of cells and tissues of plants and animals ...
Victor Von Ebner
... In 1866 he earned his doctorate from Vienna, later becoming a professor of histology and developmental history at the University of Graz (1873), and a professor of histology at the University of Vienna (1888) ... In addition to his studies involving human anatomy and histology, he was also author of works with zoological and botanical themes ...
Luis Simarro Lacabra
... From 1880 he lived in Paris and studied general anatomy and histology with Louis-Antoine Ranvier and clinical neurology under Jean Martin Charcot ... his work in psychiatry, Simarro is largely remembered for a contribution made in histology when he developed a silver bromide modification of Camillo Golgi's silver chromate technique ... and mentioned that it was a milestone that allowed him to abandon general histology and to focus on neurohistology ...
Histology - Artifacts - Post-histology
... are caused in a laboratory the majority of post histology artifacts can be avoided or removed after being discovered ...