title: The effect of relaxin supplementation of in vitro maturation medium on the development of cat oocytes obtained from ovaries stored at 4°C.
abstract: Relaxin is a member of the insulin-like family of hormones that promotes growth in a number of reproductive tissues, including the granulosa and theca cells. Cat oocytes collected from cold-stored ovaries remain capable of maturing in vitro, but the developmental ability of the oocytes decreases after 24h of cold storage. To improve the developmental ability of cat oocytes from cold-stored ovaries, we investigated the effect of relaxin supplementation of maturation medium on their meiotic ability and subsequent development. Cat oocytes were collected from ovaries stored at 4°C for one day and cultured in maturation medium supplemented with different concentrations (0, 10, 20, and 40ng/ml) of relaxin for 24h. They were then fertilized in vitro for 12h with frozen-thawed spermatozoa. After in vitro fertilization, the zygotes were cultured in synthetic oviduct fluid medium for 8 days. There were no significant differences in the maturation rates and glutathione contents of oocytes among the groups, irrespective of relaxin supplementation. The rate of blastocyst formation from oocytes matured with 10ng/ml relaxin (16.0%) was higher (p<0.05) than that from oocytes matured without relaxin (5.9%). Our findings indicate that supplementation of 10ng/ml relaxin into maturation medium may improve blastocyst formation of cat oocytes after in vitro fertilization.
authors.affiliation: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Vien Viet
authors.initials: VV
authors.lastname: Luu
authors.forename: Keisuke
authors.initials: K
authors.lastname: Hanatate
authors.forename: Fuminori
authors.initials: F
authors.lastname: Tanihara
authors.forename: Yoko
authors.initials: Y
authors.lastname: Sato
authors.forename: Lanh Thi Kim
authors.initials: LT
authors.lastname: Do
authors.forename: Masayasu
authors.initials: M
authors.lastname: Taniguchi
authors.forename: Takeshige
authors.initials: T
authors.lastname: Otoi
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002415:Cats; D015925:Cryopreservation / Q000662:veterinary; D003470:Culture Media / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D046149:Embryo Culture Techniques / Q000379:methods*; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D009865:Oocytes / Q000187:drug effects / Q000254:growth & development*; D010053:Ovary / Q000166:cytology; D012065:Relaxin / Q000494:pharmacology*; D027724:Reproductive Techniques, Assisted
chemical_list: D003470:Culture Media; D012065:Relaxin