A new in vitro model system for the study of luteinizing hormone receptor down-regulation.
The overall goal of our research is to elucidate the cellular mechanisms involved in the process of luteinizing hormone (LH)-stimulated down-regulation of the LH receptor. Towards this end, we became interested in determining whether cultured granulosa cells could be used as a physiologic model system to study this important process. In this report, we show that a very brief exposure (2 min) to physiologic concentrations of LH causes down-regulation of the LH receptor in granulosa cells cultured in serum-free medium. These data represent the first in vitro demonstration of down-regulation of the LH receptor in the granulosa cell. Furthermore, the dose dependency and kinetics of down-regulation of the LH receptor in vitro, as described here, are very similar to those reported for LH receptor down-regulation in vivo. Thus, this granulosa cell culture system is a powerful new model for studying the biochemical events involved in LH receptor down-regulation.
D000818:Animals; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004054:Diethylstilbestrol / Q000494:pharmacology; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006064:Gonadotropins, Equine / Q000494:pharmacology; D006107:Granulosa Cells / Q000187:drug effects / Q000378:metabolism*; D013006:Growth Hormone / Q000494:pharmacology; D007016:Hypophysectomy; D007986:Luteinizing Hormone / Q000378:metabolism* / Q000494:pharmacology; D011388:Prolactin / Q000494:pharmacology; D051381:Rats; D011956:Receptors, Cell Surface / Q000187:drug effects / Q000378:metabolism*; D011974:Receptors, LH
D006063:Chorionic Gonadotropin; D006064:Gonadotropins, Equine; D011956:Receptors, Cell Surface; D011974:Receptors, LH; D004054:Diethylstilbestrol; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013006:Growth Hormone