Studies in reproductive endocrinology
Spitz, Irving M
1. Studies in patients with isolated pituitary hormone deficiency The hypothalamic-portal blood system was first described by Poppa and Fielding in 1930 (1)’. It was Green and Harris (2) who initially proposed that the hypothalamus controlled anterior pituitary function by secreting regulatory factors into the hyoothalamic-portal circulation. The ultimate proof of this hypothesis was supplied in 1970 by the groups of Roger Guillemin (3) and Andrew Schally (4) who, working independently, isolated and synthesized the first hypothalamic releasing hormone known as thyrotropin-releasing hormone (TRH). Subsequently Schally and coworkers (5) isolated and synthesized luteinizing hormone-releasing hormone (LHRH). Thi.s wa > shown to be a decapeptide and it stimulated the secretion of both pituitary gonadotropins, luteinizing hormone (LH) and follicle stimulating hormone (FSH). Since LHRH releases LH as well as FSH, it has become customary to refer to this hypothalamic releasing hormone as Gonadotropin hormone releasing hormone (GnRH). Soon after synthetic GnRH became available, my attention was drawn to the evaluation of patients who presented with isolated anterior pituitary hormone deficiency. This may be defined as selective deficiency of a pituitary hormone with the rest of the gland retaining normal function. One such example is isolated bihormonal gonadotropin deficiency, which is also known as hypogonadotropic hypogonadism. This is characterized by low circulatory levels of both LH and FSH.