title: Synergetic effects of epidermal growth factor and estradiol on cytoplasmic maturation of porcine oocytes.
abstract: This study was conducted to examine the effect of epidermal growth factor (EGF) and 17beta-estradiol (E2) on nuclear and cytoplasmic (male pronuclear formation and early embryo development) maturation of porcine oocytes. Oocytes were aspirated from antral follicles and cultured in modified TCM-199 medium supplemented with 0.57 mM cysteine, 10 IU/ml eCG, 10 IU/ml hCG, with or without EGF and/or E2. In vitro fertilisation of matured oocytes was performed in a modified Tris-buffered medium (mTBM) with frozen-thawed ejaculated spermatozoa. Oocytes were transferred to NCSU-23 supplemented with 0.4% bovine serum albumin at 6 h after in vitro fertilisation. Significantly higher (p < 0.05) rates of nuclear maturation, pronuclear formation and cleavage (91.7%, 65.2% and 37.3%, respectively) were observed when oocytes were cultured in the medium containing both EGF (10 ng/ml) and E2 (1 microg/ml) than in the medium supplemented with either EGF or E2 or without both. Intracellular glutathione concentration in the oocytes cultured in the medium containing both E2 and EGF was also significantly higher (12.1 pmol per oocyte) than that of oocytes cultured in the medium with E2 or EGF alone or without both. These findings suggested that EGF and E2 have a synergestic effect on both nuclear and cytoplasmic maturation of porcine oocytes.
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Yong-Hai
authors.initials: YH
authors.lastname: Li
authors.forename: Rui-Hua
authors.initials: RH
authors.lastname: Liu
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Jiao
authors.forename: We-Hua
authors.initials: WH
authors.lastname: Wang
mesh_terms: D000818:Animals; D002970:Cleavage Stage, Ovum; D016895:Culture Media, Serum-Free; D004815:Epidermal Growth Factor / Q000378:metabolism*; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D005978:Glutathione / Q000378:metabolism; D008540:Meiosis / Q000502:physiology; D009865:Oocytes / Q000378:metabolism*; D013552:Swine / Q000378:metabolism*
chemical_list: D016895:Culture Media, Serum-Free; D004958:Estradiol; D004815:Epidermal Growth Factor; D005978:Glutathione