Cushing's Phenomenon

In 1925, the famous physician John B. Xing of Stanford University discovered that castration led to a decrease in the level of male sex hormones in the blood, but not to normalization of the level of adrenocorticotropic hormone (ACTH), produced by the hypothalamus. This meant that the pituitary gland, under the control of the hypothalamus, continued to secrete huge amounts of growth hormone, which was a consequence of some other cause or several causes. Studies conducted more than two decades later showed that the dominant factor in this case was the synthesis of ACTH from a non-neuroendocrine hormone secreted in the hypothalamus.