Critical Determinants of GnRH-Gonadotrope Interactions in the Human
The study of GnRH physiology in the human has proven to be complex, with both technical and practical obstacles. Specifically, the rapid metabolism of GnRH continues to make its direct measurement in the peripheral circulation limited in utility in defining the neuroendocrine control of reproduction in the human (1, 2). The inaccessibility of the hypophyseal-portal blood supply to direct sampling also means that a series of indirect approaches must be undertaken, using several strategies to piece together a complete story of the hypothalamic control of gonadotropin function. Thus, we have chosen to use complementary approaches involving the tandem study of GnRH-deficient men as well as of normal men with intact hypothalamic pituitary axes (3).
KeywordsTestosterone Posit Estradiol Activin Hypogonadism
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