Cellular Growth in Experimental Intrauterine Growth Retardation in Rats

RNA, DNA and protein contents were measured in liver, brain and carcass of 22 fetuses with intrauterine growth retardation (IUGR) along with 28 controls. The IUGR was induced by ligation of uterine artery in one of the two uterine horns at 17 days of gestation. In IUGR, the liver and carcass weights were significantly reduced while the brain weights were comparable with the control fetuses. The total liver DNA and protein, as well as total carcass DNA, RNA and protein contents of IUGR fetuses were significantly reduced when compared with the controls. No differences in brain RNA, DNA and protein contents were observed between the two groups. These results suggest that uterine vascular insufficiency may induce fetal growth failure and that the retardation of organ growth affects the carcass and the liver. In both organs, the cell number and cell size growth were reduced. The brain growth is preferentially spared.