Promoting effect of amino acids added to a chemically defined medium on blastocyst formation and blastomere proliferation of bovine embryos cultured in vitro.
This study was conducted to elucidate the role of amino acids added singly or in groups to a chemically defined culture medium in blastocyst formation and blastomere proliferation of bovine embryos. Embryos were generated by in vitro fertilization, and blastocyst formation and hatching, and blastomere number of blastocysts were subsequently monitored after the culture of embryos in synthetic oviduct fluid medium (SOFM). First, one of four non-essential amino acids (asparagine, aspartate, glutamate or serine) was added to SOFM and, compared with no addition, a significant (P <0.05) increase in blastocyst formation was found after the addition of asparagine, aspartate, or glutamate (35-42% versus 22%). Second, one of four essential amino acids (arginine, cystine, isoleucine or leucine) was added and arginine or isoleucine greatly improved blastocyst formation (30-36% versus 16%). Third, the addition of five stimulatory amino acids (aspartate, asparagine, glutamate, arginine and isoleucine) to SOFM significantly improved blastocyst formation compared with no addition (12% versus 21%) and such value was similar to that obtained after the addition of 19 amino acids consisting of MEM amino acid solutions (21-27%). However, five amino acids yielded fewer hatched blastocysts than 19 amino acids. Finally, although five amino acids yielded more cell number of blastocysts than no addition (93 versus 74 cells per blastocyst), it was lower than that from 19 amino acids (131 cells per blastocyst). In conclusion, either single or combined addition of asparagine, aspartate, glutamate, arginine and isoleucine stimulated blastocyst formation, while other amino acids might be necessary for further stimulating blastomere proliferation and blastocyst hatching.
Department of Veterinary Medicine, Kangwon National University, Chunchon 200-701, Republic of Korea.
Eun S
ES
Lee
Yutaka
Y
Fukui
Byeong C
BC
Lee
Jeong M
JM
Lim
Woo S
WS
Hwang
D000596:Amino Acids / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001755:Blastocyst / Q000187:drug effects* / Q000378:metabolism; D002417:Cattle / Q000502:physiology*; D016895:Culture Media, Serum-Free; D005314:Embryonic and Fetal Development / Q000187:drug effects* / Q000502:physiology; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D016018:Least-Squares Analysis; D008297:Male; D011247:Pregnancy; D011446:Prospective Studies; D011897:Random Allocation
D000596:Amino Acids; D016895:Culture Media, Serum-Free