Experimental growth retardation produced by transient period of uteroplacental ischemia in pregnant Sprague-Dawley rats.
OBJECTIVE
Introduction of experimental growth retardation, which was based on the hypothesis of uteroplacental postischemic hypoperfusion, was attempted by a transient period of uteroplacental ischemia in dated-pregnant Sprague-Dawley rats.


METHODS
On day 17 of gestation right uterine horn circulation was occluded for 5 to 60 minutes in 35 dams. The fetuses were delivered by cesarean section and studied on day 21 of gestation. For each experiment the fetuses in the right horn served as the ischemia group and those in the left horn were used as the control group.


RESULTS
Statistical analysis by Wilcoxon signed-rank test demonstrated a significant decrease in the fetal weights and in the liver-to-body weight ratios, in contrast to an increase in the brain-to-body weight ratios in the 60-minute ischemia group, compared with those in the control group. This ischemia resulted in a 14% incidence of fetal deaths.


CONCLUSIONS
Ischemia of a single uterine horn circulation in pregnant rat for 60 minutes should readily serve as a suitable model for asymmetric intrauterine growth retardation.
Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo, Japan.
M
M
Tanaka
M
M
Natori
H
H
Ishimoto
T
T
Miyazaki
T
T
Kobayashi
S
S
Nozawa
D000818:Animals; D001921:Brain / Q000473:pathology; D004195:Disease Models, Animal; D005260:Female; D005317:Fetal Growth Retardation / Q000209:etiology* / Q000473:pathology; D005333:Fetus / Q000033:anatomy & histology; D007511:Ischemia / Q000150:complications*; D008099:Liver / Q000473:pathology; D009929:Organ Size; D010920:Placenta / Q000098:blood supply* / Q000473:pathology; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014599:Uterus / Q000098:blood supply*