embryogenesis An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male ...

, Rathke's pouch is an evagination at the roof of the developing mouth in front of the buccopharyngeal membrane. It gives rise to the

anterior pituitary The anterior pituitary (also called the adenohypophysis or pars anterior) is a major Organ (anatomy), organ of the endocrine system. The anterior pituitary is the glandular, Anatomical terms of location#Usage in human anatomy, anterior lobe that t ...

(adenohypophysis), a part of the

endocrine system The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant Organ (biology), organs. In vertebrat ...

Development

Rathke's pouch, and therefore the anterior pituitary, is derived from

ectoderm The ectoderm is one of the three primary germ layers formed in early embryonic development. It is the outermost layer, and is superficial to the mesoderm (the middle layer) and endoderm (the innermost layer). It emerges and originates from the o ...

. Rathke's pouch forms during the fourth week of embryonic development. It begins as an ectodermal invagination at the roof of the stomodeum, which extends dorsally towards the developing brain. The pouch eventually loses its connection with the

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

giving rise to the

. The anterior wall of Rathke's pouch proliferates, filling most of the pouch to form '' pars distalis'' and '' pars tuberalis''. The posterior wall forms '' pars intermedia''. In some organisms, the proliferating anterior wall does not fully occupy Rathke's pouch, leaving a remnant (Rathke's cleft) between the ''pars distalis'' and ''pars intermedia''. This remnant may develop into a large cyst, the Rathke's cleft cyst. This cyst typically doesn't cause symptoms, but, if large enough, it may cause vision loss,

bitemporal hemianopsia Bitemporal hemianopsia is the medical description of a type of partial blindness where vision is missing in the outer half of both the right and left visual field. It is usually associated with lesions of the optic chiasm, the area where the opt ...

, blurry vision, and dulled color vision.

Anatomy and structure

Rathke's pouch is a sac-like structure that gives rise to the pars distalis, pars intermedia, and pars tuberalis of the pituitary gland. The cells of Rathke's pouch proliferate and differentiate into various hormone-producing cells, including Somatotrophs, Lactotrophs, Corticotrophs, Thyrotrophs, and Gonadotrophs.

Clinical significance

Rathke's pouch may develop benign cysts.

Craniopharyngioma A craniopharyngioma is a rare type of brain tumor derived from pituitary gland embryonic tissue that occurs most commonly in children, but also affects adults. It may present at any age, even in the prenatal and neonatal periods, but peak inciden ...

is a neoplasm which can arise from the epithelium within the cleft. Abnormal development of Rathke's pouch can lead to various congenital disorders such as Rathke's cleft cysts. These conditions can result in pituitary dysfunction and present with symptoms such as hormonal imbalances, growth retardation, and visual disturbances.

Research and future directions

Current research on Rathke's pouch focuses on understanding the molecular mechanisms governing its development and differentiation. Advances in genetic and stem cell research hold promise for developing novel therapies for pituitary disorders resulting from Rathke's pouch malformations.

Eponym

It is named for Martin Rathke.M. H. Rathke. Entwicklungsgeschichte der Natter (Coluber natrix). Königsberg, Bornträger, 1839.

References

External links

* *
Diagram at cushings-help.com
* https://web.archive.org/web/20070930075847/http://www.lib.mcg.edu/edu/eshuphysio/program/section5/5ch2/s5ch2_2.htm {{Development of digestive system Embryology of digestive system