Ovarian Insulin-Like Growth Factor I: Basic Concepts Leading to Potential Clinical Outlets
Amongst potential novel intraovarian regulators, insulin-like growth factor I (IGF-I) has been the subject of increasingly intense investigation1. Taken together, these studies strongly suggest the existence of an intraovarian autocrine control mechanism, wherein IGF-I may serve as the central signal, and the granulosa cell its site of production, reception, and action. In doing so, IGF-I may promote the replication and/or cytodifferentiation of the developing granulosa cell, acting largely (but not exclusively) as an amplifier of gonadotropin action. Furthermore, IGF-I (presumptively of granulosa cell origin) may also provide paracrine input to the adjacent theca-interstitial cell compartment in the interest of coordinated follicular development.
KeywordsCholesterol Estrogen Polypeptide Progesterone Androgen
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