Effect of gonadotrophin stimulation on mouse oocyte quality and subsequent embryonic development in vitro

• Published in: Reproductive biomedicine online Vol. 12; no. 3; pp. 304 - 314
• Main Authors: Wang, Yue, Ock, Sun-A, Chian, Ri-Cheng
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.03.2006
• Subjects: Animals; Benzimidazoles; Blastocyst - cytology; Blastocyst - drug effects; Blastocyst - physiology; Cell Count; Cell Differentiation - drug effects; Cell Differentiation - physiology; Chorionic Gonadotropin - pharmacology; Comet Assay; development; DNA Fragmentation - drug effects; DNA Fragmentation - physiology; Embryonic Development - drug effects; Embryonic Development - physiology; Female; Fertilization in Vitro - standards; gonadotrophin; Gonadotropins, Equine - pharmacology; In Vitro Techniques; IVF; IVM; Male; Mice; Microscopy, Fluorescence; mouse oocyte; Oocytes - cytology; Oocytes - drug effects; Oocytes - physiology; Propidium; Superovulation - drug effects; Superovulation - physiology; gonadotrophin; IVF; IVM; development; mouse oocyte
• ISSN: 1472-6483; 1472-6491
• DOI: 10.1016/S1472-6483(10)61002-4

In-vivo-matured oocytes were collected from naturally ovulated and superovulated [pregnant mare's serum gonadotrophin (PMSG) + human chorionic gonadotrophin (HCG)] mice. Immature oocytes were retrieved from naturally cycling mice and from mice primed with PMSG. The percentages of cleavage and blastocyst formation were significantly different (P < 0.05) between in-vivo- and in-vitro-matured oocytes. Blastocyst formation rate was significantly higher (P < 0.05) in immature oocytes derived from PMSG-primed mice, and the percentages of oocytes with comet tails, and their length, were significantly higher and longer respectively in in-vitro-matured oocytes. Total cell numbers of blastocysts were also significantly different (P < 0.05) between in-vivo- and in-vitro-matured oocytes, but there were also no differences in ratio of trophectoderm (TE)/inner cell mass (ICM). In conclusion, in-vivo-matured mouse oocytes were more competent than those matured in-vitro, perhaps due to a lesser degree of DNA damage. Embryonic development capacity of in-vivo-matured oocytes is not promoted by ovarian stimulation. Gonadotrophin priming prior to immature mouse oocyte retrieval is beneficial to subsequent embryonic development.