Hypothalamic regulatory hormones: physiological and clinical implications.
The hypothalamic regulatory hormones used for clinical studies are TRH, Gn-RH and somatostatin. In addition, as dopamine appears to be a physiological PIF, the dopamine agonists such as bromocriptine, could be considered as functional analogues of PIF. Gn-RH can be used to study the hypothalamic-pituitary gonadal relationship and to test the secretory reserve capacity of the gonadotrophs in disease states. Unfortunately Gn-RH testing discrimulates between pituitary and hypothalamic diseases only poorly. However gonadotrophin deficient men or women may be successfully treated with long-term Gn-RH with induction of puberty, potency, spermatogenesis and ovulation. Somatostatin has multiple actions in inhibiting endocrine and exocrine secretion but its actions are still being explored in diabetes. Bromocriptine, a long acting dopamine agonist (a functional analogue of PIF), suppresses prolactin and is highly effective in treating many hypogonadal states since hyperprolactinaemia is common. It also lowers growth hormone in acromegaly. TRH has provided a major, accurate, sensitive and safe test of thyroid function.
D004298:Dopamine / Q000502:physiology; D004700:Endocrine System Diseases / Q000188:drug therapy*; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D013006:Growth Hormone / Q000502:physiology; D013007:Growth Hormone-Releasing Hormone / Q000502:physiology; D006801:Humans; D010905:Pituitary Hormone Release Inhibiting Hormones / Q000502:physiology* / Q000627:therapeutic use; D010906:Pituitary Hormone-Releasing Hormones / Q000502:physiology* / Q000627:therapeutic use; D011389:Prolactin Release-Inhibiting Factors / Q000502:physiology; D013004:Somatostatin / Q000502:physiology; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology
D010905:Pituitary Hormone Release Inhibiting Hormones; D010906:Pituitary Hormone-Releasing Hormones; D007987:Gonadotropin-Releasing Hormone; D013004:Somatostatin; D013973:Thyrotropin-Releasing Hormone; D013006:Growth Hormone; D013007:Growth Hormone-Releasing Hormone; D011389:Prolactin Release-Inhibiting Factors; D004298:Dopamine