Submitted February 9, 2005
Returned for revision March 8, 2005
Accepted May 13, 2005
Embryo
Effects of Embryo Culture on Angiogenesis and Morphometry
of Bovine Placentas During Early Gestation
Jeremy R. Miles ,
Charlotte E. Farin ,
Karina F. Rodriguez ,
Joseph E. Alexander ,
and
Peter W. Farin *
* To whom correspondence should be addressed. E-mail: peter_farin{at}ncsu.edu.
Abstract
The objective of this study was to determine the effects
of undefined and semi-defined
culture systems for in vitro embryo production on
angiogenesis and morphometry of bovine
placentas during early gestation. Blastocysts produced in
vivo were recovered from
superovulated Holstein cows and served as controls.
Blastocysts produced in vitro were exposed
to either serum supplemented medium with cumulus cell
co-culture (in vitro-produced with
serum; IVPS) or modified synthetic oviductal fluid medium
without serum or co-culture
(mSOF). Single blastocysts from each production system
were transferred into heifers. Fetuses
and placentas were recovered on Day 70 of gestation.
Cotyledonary tissues were obtained for
quantification of vascular endothelial growth factor
(VEGF) and peroxisome proliferator
activated receptor-gamma (PPARG) mRNA and protein. Samples
of placentomes were prepared
for immunocytochemistry and histological analysis.
Placentas from the mSOF group were
heavier and had the fewest placentomes, least placental
fluid, and lowest placental efficiency
(fetal weight/placental weight) compared with the In Vivo
and IVPS groups. There was no
effect of embryo culture system on volume densities of
fetal villi or maternal endometrium
within placentomes. The volume density of fetal pyknotic
cells was increased in placentomes in
the mSOF group compared with the In Vivo and IVPS groups.
Placentomes in the mSOF group
had decreased densities of blood vessels and decreased
levels of VEGF mRNA in cotyledonary
tissue. In conclusion, compared with placentas from
embryos produced in vivo or in vitro using
an undefined culture system, placentas from embryos
produced in vitro using a semi-defined
culture system exhibited a greater degree of aberrant
development of the placenta during early
gestation.
Key words:
Embryo •
Developmental biology •
Gene regulation •
In vitro fertilization •
Placenta
