Hypothalamic–pituitary–prolactin axis peptide (VIP). Hypothalamic–pituitary–prolactin axis The hypothalamic–pituitary–prolactin axis (HPP axis), also known as the hypothalamic–pituitary–mammary axis or hypothalamic–pituitary–breast axis, is a hypothalamic–pituitary axis which includes the secretion of prolactin (PRL; luteotropin) from the lactotrophs of the pituitary gland into the circulation and the subsequent action of prolactin on tissues such as, particularly, the mammary glands or breasts. It is involved in lobuloalveolar maturation of the mammary glands during pregnancy and the induction and maintenance of lactation following parturition. Hormones that control the secretion of prolactin from the pituitary gland include dopamine ("prolactin-inhibiting factor", or "PIF"), estradiol, progesterone, thyrotropin-releasing hormone (TRH), and
Pituitary adenoma associated with Carney complex. Patients with CNC develop growth hormone (GH)-producing pituitary tumors and in some instances these same tumors also secrete prolactin. There are however no isolated prolactinomas or any other type of pituitary tumor. In some patients with CNC, the pituitary gland is characterized by hyperplastic areas with the hyperplasia most likely preceding the formation of GH-producing adenomas. Familial isolated pituitary adenoma (FIPA) is a term that is used to identify a condition that displays an autosomal dominant inheritance and is characterised by the presence of two or more related patients affected by adenomas of the pituitary gland