Effect of intracellular Ca2+ chelation with the acetoxymethyl ester-derived form of bis(o-aminophenoxy)ethane-N,N,N,N',N'-tetraacetic acid on meiotic division and chromosomal segregation in mouse oocytes.
OBJECTIVE
Our purpose was to ascertain the effect of intracellular Ca2+ chelation on the chromosomal distribution and segregation of mouse oocytes during maturation in vitro.


METHODS
Germinal vesicle oocytes were loaded with the acetoxymethyl ester-derived form of bis(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM). Chromosomal distribution and segregation of control and BAPTA-AM-treated metaphase II (MII) oocytes were evaluated at 16 hr, and intracellular ATP content at 0, 1, and 16 hr after BAPTA-AM loading.


RESULTS
BAPTA-AM treatment decreased (P < or = 0.05) the potential for in vitro maturation, increased (P < or = 0.0001) the percentage of oocytes displaying an abnormal distribution of metaphase II chromosomes in the meiosis II spindle and aneuploidy, and decreased (P < or = 0.005) the ATP content at 0, 1, and 16 hr of culture compared to the control groups.


CONCLUSIONS
These findings raise some concern about any other condition/drug that may directly or indirectly decrease the intracellular Ca2+ concentration in human oocytes.
Vendrell
F J
FJ
Department of Paediatrics, Obstetrics and Gynaecology, Faculty of Medicine, University of Valencia, Spain.
Ten
J
J
De Oliveira
M N
MN
Cano
A
A
Tarin
J J
JJ
D000255:Adenosine Triphosphate / Q000032:analysis; D000782:Aneuploidy; D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology*; D002875:Chromosomes / Q000187:drug effects*; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008540:Meiosis / Q000502:physiology*; D008677:Metaphase; D051379:Mice; D008813:Mice, Inbred ICR; D008856:Microscopy, Fluorescence; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*
C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid; D000255:Adenosine Triphosphate; D002118:Calcium