title: Gonadotropins up-regulate the expression of enolase 2, but not enolase 1, in the rat ovary.
abstract: It has been demonstrated that the glycolytic enzymes, enolase 1 (ENO1) and enolase 2 (ENO2), are expressed in the rat ovary.  In the present study, we found that mRNA levels of ovarian ENO2 but not ENO1 in normal cycling adult female rats changed significantly during the estrous cycle: ovarian ENO2 mRNA levels at metestrus were lower than those at estrus.  Single injection of human CG (hCG) or equine CG (eCG) into immature (3 week old) rats up-regulated ovarian expression of ENO2.  hCG mainly increased ENO2 expression in oocytes and theca cells of preantral and antral follicles, and eCG did in theca cells of these follicles.  In contrast, hCG and eCG did not affect the expression of ENO1, which was mainly expressed in granulosa cells.  These results suggest that endogenous gonadotropins up-regulate expression of ENO2 in oocytes and theca cells of preantral and antral follicles, which would activate glycolysis in these cells.  It is also suggested that the activated glycolysis is necessary for ovarian functions such as follicle growth and maturation, and hormone production.
authors.affiliation: Department of Obstetrics and Gynecology, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Yoshioka
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Wataru
authors.initials: W
authors.lastname: Tarumi
authors.forename: Masanori T
authors.initials: MT
authors.lastname: Itoh
authors.forename: Bunpei
authors.initials: B
authors.lastname: Ishizuka
mesh_terms: D000818:Animals; D015153:Blotting, Western; D030762:Estrous Cycle / Q000502:physiology; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006062:Gonadotropins / Q000378:metabolism*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D009865:Oocytes / Q000201:enzymology; D006080:Ovarian Follicle / Q000166:cytology / Q000201:enzymology*; D010751:Phosphopyruvate Hydratase / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013799:Theca Cells / Q000201:enzymology*; D015854:Up-Regulation
chemical_list: D006062:Gonadotropins; D012333:RNA, Messenger; C000609763:ENO1 protein, rat; D010751:Phosphopyruvate Hydratase