Optimal conditions for successful in vitro fertilization and subsequent embryonic development in Sprague-Dawley rats.
The present study was conducted to determine the optimal conditions for successful in vitro fertilization (IVF) in Sprague-Dawley (SD) rats. The IVF of oocytes from SD and Wistar rats was compared in different fertilization media (mR1ECM, IVF-20, and modified Krebs-Ringer bicarbonate solution [mKRB]), and IVF conditions were then optimized for oocytes of the SD strain. Results showed that in mR1ECM medium, fertilization rates were markedly lower in SD rats (15%) than in the Wistar strain (73%), although this response was significantly improved by increasing the NaCl concentration. In addition, fertilization rates in SD rats were higher in modified IVF-20 (73%) than in IVF-20 (18%) and mKRB (53%). In contrast, fertilization rates in Wistar rats were higher in IVF-20 and modified IVF-20 than in mKRB (78%, 74%, and 36%, respectively). Further investigation concerning the effects of the NaCl supplementation (10- 40 mM) in IVF-20 on the fertilization of oocytes in the SD strain indicated that significantly higher percentages of oocytes were fertilized in IVF-20 supplemented with 30 mM NaCl (66%) and developed to the blastocyst stage (47%) in vitro. After transfer, embryos derived from this IVF system developed to term at a percentage comparable to that of in vivo-fertilized controls. In conclusion, differences exist in optimal IVF conditions between rat strains, and a modified culture medium has been successfully developed for assessment of the developmental competence of oocytes in SD rats.
Reproductive Biology Unit and Division of Reproductive Medicine, Departments of Obstetrics & Gynecology and Cellular & Molecular Medicine, University of Ottawa, Ontario, Canada K1Y 4E9.
Jin-Yi
JY
Jiang
Benjamin K
BK
Tsang
D000818:Animals; D003470:Culture Media / Q000494:pharmacology; D046149:Embryo Culture Techniques; D005260:Female; D005298:Fertility; D005307:Fertilization in Vitro; D007552:Isotonic Solutions / Q000494:pharmacology; D008297:Male; D009865:Oocytes / Q000187:drug effects; D009994:Osmolar Concentration; D051381:Rats; D017207:Rats, Sprague-Dawley / Q000196:embryology* / Q000502:physiology; D017208:Rats, Wistar; D012965:Sodium Chloride / Q000494:pharmacology; D013045:Species Specificity
D003470:Culture Media; D007552:Isotonic Solutions; C051865:Krebs-Ringer solution; D012965:Sodium Chloride