Induction of fetal malformations after treatment of mouse embryos with methylnitrosourea at the preimplantation stages

Nagao, T; Morita, Y; Ishizuka, Y; Wada, A; Mizutani, M

HERO ID

66989

Reference Type

Journal Article

Year

1991

Language

English

PMID

1677493

HERO ID 66989
In Press No
Year 1991
Title Induction of fetal malformations after treatment of mouse embryos with methylnitrosourea at the preimplantation stages
Authors Nagao, T; Morita, Y; Ishizuka, Y; Wada, A; Mizutani, M
Journal Birth Defects Research, Part B: Developmental and Reproductive Toxicology
Volume 11
Page Numbers 1-10
Abstract The effects of methylnitrosourea (MNU) on the development of preimplantation mouse embryos were investigated in this study. ICR mice were treated intraperitoneally with single doses of 10, 20, and 30 mg MNU/kg body wt on day 0, 1, 2, or 3 of pregnancy. The uterine contents were examined on day 18 of pregnancy. The fetuses were examined for external and skeletal abnormalities. No significant differences were observed in the number of implantation sites between all the MNU-treated groups and controls. MNU treatment on day 2 or 3 of pregnancy caused dose-dependent significant increases in the incidence of abnormal fetuses over the control level, while treatment on day 0 or 1 failed to cause an increase of abnormalities. Cleft palate, exencephalus, and malformed vertebrae were the most common types of abnormalities. In the embryo transfer experiments, the frequency of fetal abnormalities induced when embryos were transferred from MNU-treated females to untreated pseudopregnant females was significantly higher than that induced when embryos were transferred from untreated females to MNU-treated or untreated pseudopregnant females. The results in the present study confirm and extend the previously proposed hypothesis that the direct effects of MNU on preimplantation embryos make a significant contribution to the induction of fetal malformations.
Doi 10.1002/tcm.1770110102
Pmid 1677493
Wosid WOS:A1991FD12400001
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Is Peer Review Yes