Successful in vitro growth of rat two-cell embryos to blastocysts using a simple chemically defined medium

• Published in: Journal of pharmacological and toxicological methods Vol. 43; no. 3; pp. 171 - 175
• Main Authors: Goh, V.H.H., Adiga, S.K., Tain, C.F., Tong, T.Y.Y., Ng, S.C.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-05-2000
• Subjects: Animals; Blastocyst - drug effects; Blastocyst - physiology; Blastocyst formation; blastocysts; Culture Media; Culture Techniques; Embryonic and Fetal Development - drug effects; Embryonic and Fetal Development - physiology; Female; Glucose - pharmacology; Glutamine - pharmacology; In vitro culture; Pregnancy; R2ECM; Rat embryo; Rats; Rats, Wistar; Rat embryo; Blastocyst formation; In vitro culture; R2ECM
• ISSN: 1056-8719; 1873-488X
• DOI: 10.1016/S1056-8719(00)00084-8

The aim of the present study was to formulate a simple chemically defined medium for the in vitro growth of rat two-cell embryos to blastocysts. Embryos from day 2 pregnant rats were retrieved and placed in paraffin oil-covered droplets of “rat two-cell embryo culture medium” (R2ECM) containing combinations of various serum supplements, glucose,
l-glutamine, and cultured up to 96 h in a CO
2 incubator. Embryos cultured in the basic medium (R2ECM), as well as those supplemented either with fetal bovine serum (FBS) or male rat serum (MRS) did not develop beyond the two- to four-cell stage. In R2ECM with 0.3% bovine serum albumin (BSA) and 7.5 mM glucose, 44% of embryos reached the blastocyst stage by 96 h in culture, and the blastulation rate increased to about 83% when 1 mM of
l-glutamine was added. To evaluate the effects of varying doses of glucose, two-cell embryos were cultured in R2ECM supplemented with 0.3% BSA, 1 mM
l-glutamine, and 2.5, 5.0, or 7.5 mM of glucose. The percentage of embryos reaching the blastocyst stage for 2.5, 5.0, and 7.5 mM glucose was 64.6%, 65.3%, and 82.9%, respectively. The present study showed that the modified medium (R2ECM) is a simple chemically defined medium that is capable of supporting in vitro growth of rat two-cell embryos to blastocysts in high proportion (greater than 80%) without the need for change of medium within 96 h of culture.