title: Comparison between effects of 3-isobutyl-1-methylxanthine and FSH on gap junctional communication, LH-receptor expression, and meiotic maturation of cumulus-oocyte complexes in pigs.
abstract: We investigated cAMP content, gap junctional communications (GJCs) status, and LH-receptor (LH-R) expression in porcine cumulus-oocyte complexes (COCs) during in vitro maturation treated with the phosphodiesterase (PDE) inhibitor 3-isobutyl-1-methylxanthine (IBMX) or with FSH. COCs were cultured for 20 hr (1st culture) in M199 containing 10% FBS (basic medium, BM group) or BM supplemented with FSH (FSH group) or IBMX (IBMX group). Each COC was then transferred into BM containing both FSH and LH and cultured for an additional 24 hr (2nd culture). The proportions of metaphase-II (M-II) oocytes at the end of the 2nd culture did not differ between the FSH (75.7%) and IBMX (68.2%) groups, whereas only 10.1% of oocytes in the BM group reached the M-II stage. During the 1st culture, the cAMP content of COCs and oocytes became significantly higher in the FSH and IBMX groups than in the BM group; the FSH group had a far greater increment than did the IBMX group. GJCs in the FSH and BM groups gradually closed with increasing duration of the 1st culture, whereas a significantly higher proportion of COCs in the IBMX group still had open GJCs than in the other two groups. Furthermore, LH-R mRNA expression significantly increased in both the FSH and IBMX groups compared with the BM group. These results suggest that inhibition of PDEs in porcine COCs make the oocyte ready for release from meiotic arrest, and that maintenance of a moderate cAMP content may prolong GJCs and stimulate LH-R expression.
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan. semil@nias.affrc.go.jp
authors.forename: Manabu
authors.initials: M
authors.lastname: Ozawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagai
authors.forename: Tamás
authors.initials: T
authors.lastname: Somfai
authors.forename: Michiko
authors.initials: M
authors.lastname: Nakai
authors.forename: Naoki
authors.initials: N
authors.lastname: Maedomari
authors.forename: Mokhamad
authors.initials: M
authors.lastname: Fahrudin
authors.forename: Ni Wayan Kurniani
authors.initials: NW
authors.lastname: Karja
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kaneko
authors.forename: Junko
authors.initials: J
authors.lastname: Noguchi
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Ohnuma
authors.forename: Noriko
authors.initials: N
authors.lastname: Yoshimi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Miyazaki
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kikuchi
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology*; D000818:Animals; D002450:Cell Communication / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D054885:Cumulus Cells / Q000166:cytology / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D017629:Gap Junctions / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000502:physiology; D008540:Meiosis / Q000187:drug effects* / Q000502:physiology; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis; D011974:Receptors, LH / Q000096:biosynthesis*; D013552:Swine
chemical_list: D010726:Phosphodiesterase Inhibitors; D012333:RNA, Messenger; D011974:Receptors, LH; D005640:Follicle Stimulating Hormone; D000242:Cyclic AMP; D015056:1-Methyl-3-isobutylxanthine