title: The effects of extracellular ATP and its receptor antagonists on pig oocytes during in vitro maturation.
abstract: We measured the ATP concentrations in the porcine follicular fluid derived from three sizes of follicles (small: 6 mm in diameter). Then, the effects of pre-treatment (100 μM each for 30 min before maturation) with antagonists for extracellular ATP receptor P2X or P2Y on the nuclear maturation rate of cumulus-cell-enclosed (COs) or -denuded oocytes (DOs) up to the preovulatory stage in the presence or absence of 20 nM ATP (a similar concentration to that of medium-sized follicle fluid) were investigated. The antagonists used were pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS) or reactive blue 2 (RB2), for extracellular ATP receptor P2X and P2Y, respectively. In addition, the embryonic development rates of COs pre-treated with RB2 were also evaluated. It was found that when the follicular sizes increased, the ATP concentrations significantly decreased (P < 0.05). No differences were observed in the nuclear maturation rates among all COs, regardless of pre-treatment with (+) or without (-) PPADS and in the presence (+) or absence (-) of ATP during maturation. In contrast, the nuclear maturation rate of the COs, but not DOs, in the ATP(-) RB2(+) group was significantly lower (P < 0.05) than that of the ATP(-) RB2(-) and ATP(+)RB2(-) groups. The pronuclear formation and blastocyst formation rates by parthenogenetic activation in the ATP(-) RB2(+) and ATP(+) RB2(+) groups were significantly lower (P < 0.05) than those in the ATP(-) RB2(-) group. In conclusion, it is suggested that the nuclear maturation of porcine oocytes may be influenced by the ATP receptor P2Y present in the cumulus cells.
authors.affiliation: Animal Reproduction Laboratory,Faculty of Agriculture,University of Miyazaki,Miyazaki 889-2192,Japan.
authors.forename: Erika
authors.initials: E
authors.lastname: Wakizoe
authors.affiliation: Animal Reproduction Laboratory,Faculty of Agriculture,University of Miyazaki,Miyazaki 889-2192,Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Ashizawa
authors.affiliation: Division of Bio-Resources,Frontier Research Center,University of Miyazaki889-1692,Japan.
authors.forename: Shinsuke H
authors.initials: SH
authors.lastname: Sakamoto
authors.affiliation: Sumiyoshi Livestock Station,Field Science Center,Faculty of Agriculture,University of Miyazaki,Miyazaki 880-0121,Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Hemmi
authors.affiliation: Sumiyoshi Livestock Station,Field Science Center,Faculty of Agriculture,University of Miyazaki,Miyazaki 880-0121,Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Kobayashi
authors.affiliation: Animal Reproduction Laboratory,Faculty of Agriculture,University of Miyazaki,Miyazaki 889-2192,Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tsuzuki
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001755:Blastocyst / Q000502:physiology; D054885:Cumulus Cells / Q000166:cytology / Q000187:drug effects; D005260:Female; D015571:Follicular Fluid / Q000737:chemistry / Q000378:metabolism; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods*; D008297:Male; D009865:Oocytes / Q000187:drug effects* / Q000502:physiology*; D006080:Ovarian Follicle / Q000187:drug effects; D010312:Parthenogenesis; D058919:Purinergic P2 Receptor Antagonists / Q000494:pharmacology*; D011732:Pyridoxal Phosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D018048:Receptors, Purinergic P2 / Q000378:metabolism; D058470:Receptors, Purinergic P2Y / Q000378:metabolism; D034421:Sus scrofa; D013552:Swine; D014227:Triazines / Q000494:pharmacology
chemical_list: D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D058470:Receptors, Purinergic P2Y; D014227:Triazines; C077792:pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid; C012842:Cibacron Blue F 3GA; D011732:Pyridoxal Phosphate; D000255:Adenosine Triphosphate
keywords: Antagonist; Extracellular ATP; In vitro maturation; P2Y receptor; Porcine oocytes