open access

https://hdl.handle.net/2115/64619

Expression of Membrane Progestin Receptors (mPRs) in Granulosa Cells of Medaka Preovulatory Follicles

英語

expression

2016-02

日本動物学会

Zoological science

33(1)

98-105

Membrane progestin receptor (mPR) alpha on the cell membrane of the oocyte is involved in the meiotic maturation of vertebrates, including teleosts, but little is known about the role of this membrane-bound follicular receptor. We investigated the ovarian expression of membrane progestin receptor (mPR) mRNA in medaka. In follicles that were destined to ovulate, transcripts of mPR alpha and mPR gamma were expressed in the oocytes as well as the granulosa cells. Transcripts of mPR alpha and mPR gamma were expressed at relatively constant levels in the whole ovary and in the preovulatory follicles throughout the 24-h spawning cycle. In vitro incubation of the preovulatory follicles with recombinant medaka luteinizing hormone caused no significant changes in the expression of mPRa alpha and mPR gamma mRNA, suggesting LH-independent follicular expression of these mPR genes. Using HEK293T cells expressing medaka mPRs, forskolin-elevated intracellular cAMP levels were found to be reduced on treatment of the cells with ligand 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (DHP), but only in the cells expressing mPRaa. These results indicate that activation of mPRaa and mPR gamma with DHP may cause differential effects on the granulosa cells. Information obtained from the present study may help to elucidate the role of mPR alpha and mPR gamma in the granulosa cells of the follicles.

学術雑誌論文

Version of Record

0289-0003