Ovulation is perhaps the most fundamental event in reproduction. It requires a dramatic 20-30-fold surge of luteinizing hormone (LH) released by the anterior pituitary into the peripheral circulation to induce the release of the egg from the ovary. The secretion of LH from the pituitary is cued by the hypothalamic neuropeptide, gonadotropin-releasing hormone (GnRH). The secretion of GnRH from the brain and its interpretation by gonadotropes in the pituitary therefore constitute the essential central events for reproductive competence in virtually all vertebrates. Key aspects of LH surge regulation must still be elucidated. The current dogma states that the pituitary is a relatively passive player receiving hypothalamic direction (GnRH) and turning out pituitary product (LH) that simply leaks into the peripheral circulation upon release. This SGER project seeks to establish that cells in the pituitary respond to GnRH by physically moving to maximize their access to release their LH. This finding will alter the prevailing dogma by proclaiming that the pituitary is no longer a passive player in the process, but rather plays a dynamic role in creating an ovulatory surge of LH. If this phenomenon were more generalized, this concept would fundamentally change current concepts of endocrine organ signaling. The broader impacts of the proposed research stretch from the involvement of students at all levels of the educational process (K-12, undergraduate, graduate, postdoctoral), to Colorado State University's commitment as a land grant institution to public service, to the novelty and biological significance of the proposed research.
