Rathke s pouch

The adenohypophysis is derived embryonically from glandular tissue, specifically, Rathke s pouch. This tissue originates from the oropharynx, or the roof of the mouth. It then migrates toward the embryonic nervous tissue destined to form the neurohypophysis. When these two tissues come into contact, Rathke s pouch loses its connection with the roof of the mouth and the pituitary gland is formed. Unlike the neurohypophysis, which releases hormones originally synthesized in the hypothalamus, the adenohypophysis synthesizes its own hormones in specialized groups of cells. Similar to the neurohypophysis, however, the release of these hormones into the blood is regulated by the hypothalamus. 

Small cysts that develop within the sella at the expense of remnants of Rathke s pouch... 

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