Posterior pituitary pituitary. A few sources include the pars intermedia as part of the posterior lobe, but this is a minority view. It is based upon the gross anatomical separation of the posterior and anterior pituitary along the cystic remnants of Rathke's pouch, causing the pars intermedia to remain attached to the neurohypophysis. Two hormones are classically considered as being related to the posterior pituitary: oxytocin and vasopressin. These hormones are created in the hypothalamus and released in the posterior pituitary. After creation, they are stored in neurosecretory vesicles regrouped into Herring bodies before being secreted in the posterior pituitary via the
Pituitary stalk tract. It has been thought that the pituitary stalk may become compressed due to suprasellar tumors in the pars tuberalis region, and that the resulting compression may cause hyperprolactinemia. This phenomenon has been described as the stalk effect or pituitary stalk compression syndrome. However, at least one article suggests that the increase in prolactin in these cases may instead be caused by the tumor's secretion of preprotachykinin A-derived tachykinins, substance P, and/or neurokinin A. Damage to the pituitary stalk blocks the release of antidiuretic hormone, resulting in polydypsia (abusive water intake) and polyuria (excessive urination). Pituitary stalk The pituitary stalk