VOLUME 1, ISSUE 2, P106-112, NOVEMBER 01, 2020
Robert W. Rebar, M.D.
The story of the gonadotropins begins early in the twentieth century, when several clinicians reported that destructive lesions of the anterior pituitary gland resulted in several untoward effects, including gonadal atrophy. However, the critical role of the anterior pituitary gland in stimulating and maintaining gonadal function was established by means of a series of classic experiments in animals. The first experimental evidence was provided in 1910 by Harvey Cushing’s group, who demonstrated the effects of hypophysectomy in dogs (1). In 1921, Evans and Long reported that the intraperitoneal injection of anterior pituitary extracts could alter the estrus cycle and stimulate growth in rats (2). In 1927, Smith and Engle noted that anterior pituitary extracts could induce precocious puberty in immature rats and mice (3). Smith also reported that young hypophysectomized rats replaced with anterior pituitary extracts did not undergo gonadal atrophy or atrophy of the thyroid and adrenal gland (4).