Evidence for Separate Corticotrophin- and Luteinizing Hormone-Releasing Factors in Hypothalamic Extracts

Abstract
Summary 1. Several fractions obtained after gel filtration of beef (and sheep) stalk-median eminence tissue were active in releasing LH as judged by their ability to evoke OAAD in immature rats pretreated with gonadotropins and to increase plasma LH in ovariectomized, estrogen progesterone-blocked rats. These same fractions failed to release ACTH even when the dose of extract was increased by a factor of five. 2. A frac-