Posterior pituitary bloodstream. Insufficient secretion of vasopressin underlies diabetes insipidus, a condition in which the body loses the capacity to concentrate urine. Affected individuals excrete as much as 20 liters of dilute urine per day. Oversecretion of vasopressin causes the syndrome of inappropriate antidiuretic hormone (SIADH). Posterior pituitary The posterior pituitary (or neurohypophysis) is the posterior lobe of the pituitary gland which is part of the endocrine system. The posterior pituitary is not glandular as is the anterior pituitary. Instead, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary, and serve as a site
Pituitary apoplexy can be applied as a nose spray or taken by mouth. Pituitary apoplexy is rare. Even in people with a known pituitary tumor, only 0.6–10% experience apoplexy; the risk is higher in larger tumors. Based on extrapolations from existing data, one would expect 18 cases of pituitary apoplexy per one million people every year; the actual figure is probably lower. The average age at onset is 50; cases have reported in people between 15 and 90 years old. Men are affected more commonly than women, with a male-to-female ratio of 1.6. The majority of the underlying tumors are "null cell"