THE EFFECT OF MATERNAL RESTRAINT ON DEVELOPMENTAL TOXICITY OF ALUMINUM IN MICE

Both aluminum (Al) and maternal restraint have been reported to cause developmental toxicity in mammals. This study assessed in pregnant mic e the potential interaction between Al and maternal restraint. Four gr oups of plug-positive female mice were given LP injections of AlCl3 at 37.5 and 75 mg/kg/day on days 6-15 of gestation. Two of these groups were also subjected to restraint for 2 h/day during the same gestation al days. Control groups included restrained and unrestrained pregnant mice nonexposed to Al. Cesarean sections were performed on gestation d ay 18, and the fetuses were weighed and examined for morphological def ects. Maternal toxicity was significantly enhanced by restraint at 75 mg AlCl3/kg/day. No increases in the number of resorptions or dead fet uses per litter were observed following exposure to Al, maternal restr aint, or combined Al and restraint. However, a significant decrease in fetal body weight, as well as a significant increase in the number of litters with morphologic defects, was observed in the group exposed t o 75 mg AlCl3/kg/day plus maternal restraint. The current results sugg est that maternal restraint could enhance the metal-induced developmen tal toxicity (reduced fetal body weight, increase in the number of lit ters with morphologic defects) only at high doses of the metal, which are also toxic to the dam. (C) 1998 Elsevier Science Inc.