title: The effects of EGF and IGF-1 on FSH-mediated in vitro maturation of domestic cat oocytes derived from follicular and luteal stages.
abstract: The objective of this study was to evaluate the influence of epidermal growth factor (EGF) and insulin like growth factor-I (IGF-1) on the in vitro maturation of cat oocytes recovered from follicular and luteal stage ovaries. Oocytes from follicular (n=580) and luteal (n=209) stages were harvested and divided into four groups, which were cultured in FSH-mediated maturation medium supplemented with: (1) EGF alone (25ng/mL); (2) IGF-1 alone (100ng/mL); (3) EGF+IGF-1 (25ng/mL EGF+100ng/mL IGF-I); or (4) no growth factor (control). The proportion of follicular stage oocytes reaching the metaphase II stage was significantly higher than that of oocytes obtained at the luteal stage in both control and study groups (p<0.001). The percentages of oocytes reaching the metaphase II stage during the follicular period were 62.6% in control; 70.9% in EGF; 72.8% in IGF-1, and 78.1% in EGF+IGF-1 groups, whereas the respective values for gametes collected from luteal stage ovaries were 12.5%, 17.5%, 12.5%, and 16.9%. Additionally, the differences between the study and control groups were significant in the case of follicular stage oocytes. Finally, supplementing the maturation medium with EGF and/or IGF-1 significantly enhanced the meiotic maturation of oocytes recovered from follicular stage ovaries. The present study also demonstrated that the combination of EGF and IGF-I provides an additional or synergic effect on meiotic maturation of oocytes recovered from the follicular stage.
authors.affiliation: Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
authors.forename: Koray
authors.initials: K
authors.lastname: Yıldırım
authors.affiliation: Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey. Electronic address: vural@ankara.edu.tr.
authors.forename: M Rıfat
authors.initials: MR
authors.lastname: Vural
authors.affiliation: Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
authors.forename: Sükrü
authors.initials: S
authors.lastname: Küplülü
authors.affiliation: Department of Histology and Embriology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
authors.forename: Ziya
authors.initials: Z
authors.lastname: Ozcan
authors.affiliation: Department of Obstetrics, Gynaecology and Reproduction, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
authors.forename: I Mert
authors.initials: IM
authors.lastname: Polat
mesh_terms: D000818:Animals; D002415:Cats; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005260:Female; D005498:Follicular Phase / Q000502:physiology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008183:Luteal Phase / Q000502:physiology; D009865:Oocytes / Q000187:drug effects* / Q000254:growth & development
chemical_list: D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I
keywords: Cat oocytes; EGF; IGF-I; In vitro maturation