Inhibitory effect of phosphate on in vitro development of 2-cell rat embryos is overcome by a factor(s) in oviductal extracts.
It has been found that inorganic phosphate (P) at concentrations as low as 10 microM markedly inhibits in vitro development of early rat embryos at the 1-cell or 2-cell stage to the blastocyst stage, although P is present at concentrations of 0.37-1.19 mM in oviductal fluid, in which the development of early embryos occurs. We show here that fractions (PTF, 50-250 microg/ml) of rat oviductal extracts (OVEs) passed through a Blue CL6B affinity column have the ability to overcome the inhibitory effects of P on the development of 2-cell rat embryos in a dose-dependent manner, whereas 250 microg/ml OVE or 250 microg/ml of the bound fractions (BF) induced degenerative changes in the embryos at the 2-cell stage. Moreover, PTF at concentrations of >/=100 microg/ml stimulated the hatching of blastocysts both in medium with and without P, although none of the blastocysts in medium without PTF hatched from their zona pellucida.
Yamada
M
M
Laboratory of Reproductive Physiology, Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto, Japan. yamada@jkans.jkans.kais.kyoto-u.ac.jp
Nishikimi
A
A
D000818:Animals; D001685:Biological Factors / Q000494:pharmacology*; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D005187:Fallopian Tubes / Q000187:drug effects* / Q000196:embryology; D005260:Female; D010755:Organophosphates / Q000494:pharmacology*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D015044:Zona Pellucida / Q000187:drug effects* / Q000378:metabolism
D001685:Biological Factors; D010755:Organophosphates