endocrine and metabolic disorders
Overview of the Endocrine System
Hypothalamic Controls
Thus far, 7 physiologically important hypothalamic neurohormones have been identified (see table Hypothalamic Neurohormones ). Except for the biogenic amine Neurohormones may control the release of multiple pituitary hormones. Regulation of most anterior pituitary hormones depends on stimulatory signals from the hypothalamus; the exception is prolactin, which is regulated by inhibitory stimuli. If the pituitary stalk (which connects the pituitary to the hypothalamus) is severed, prolactin release increases, whereas release of all other anterior pituitary hormones decreases. Many hypothalamic abnormalities (including tumors and encephalitis and other inflammatory lesions) can alter the release of hypothalamic neurohormones. Because neurohormones are synthesized in different centers within the hypothalamus, some disorders affect only one neuropeptide, whereas others affect several. The result can be undersecretion or oversecretion of neurohormones. Clinical syndromes that result from the ensuing pituitary hormone dysfunction (eg, ArginineVasopressin Deficiency (Central Diabetes Insipidus) , 