title: Endothelin-2 in ovarian follicle rupture.
abstract: The ovulatory process is activated by a surge of LH, a pituitary gonadotropin, which initiates a cohort of dramatic changes in biochemical, physical, and gene expression in the ovary, leading to follicle rupture and oocyte release. Here we report the identification of endothelin-2 (EDN2) as a last moment-trigger of follicle rupture. In the ovary, EDN2 is exclusively and transiently expressed in the granulosa cells immediately before ovulation. Administration of EDN2 to the ovarian tissue induced rapid contraction, whereas addition of tezosentan, an endothelin receptor antagonist, diminishes the EDN2 effect. In vivo, treatment of tezosentan before ovulation substantially decreases gonadotropin-induced superovulation. As a target tissue of EDN2 action, we identified a layer of smooth muscle cells in the follicular wall of each follicle. Taken together, our data indicate that EDN2 induces follicular rupture by constricting periovulatory follicles.
authors.affiliation: Department of Clinical Sciences, University of Kentucky, Lexington, 40536, USA. cko2@uky.edu
authors.forename: Chemyong
authors.initials: C
authors.lastname: Ko
authors.forename: Mary C
authors.initials: MC
authors.lastname: Gieske
authors.forename: Linah
authors.initials: L
authors.lastname: Al-Alem
authors.forename: Yunkyung
authors.initials: Y
authors.lastname: Hahn
authors.forename: Wen
authors.initials: W
authors.lastname: Su
authors.forename: Ming C
authors.initials: MC
authors.lastname: Gong
authors.forename: Marc
authors.initials: M
authors.lastname: Iglarz
authors.forename: Yongbum
authors.initials: Y
authors.lastname: Koo
mesh_terms: D000818:Animals; D019332:Endothelin-1 / Q000502:physiology; D019333:Endothelin-2 / Q000235:genetics / Q000502:physiology*; D019334:Endothelin-3 / Q000502:physiology; D047628:Estrogen Receptor alpha / Q000502:physiology; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000502:physiology; D006080:Ovarian Follicle / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017466:Receptors, Endothelin / Q000502:physiology
chemical_list: D019332:Endothelin-1; D019333:Endothelin-2; D019334:Endothelin-3; D047628:Estrogen Receptor alpha; D012333:RNA, Messenger; D017466:Receptors, Endothelin