Ornithine decarboxylase activity in the neonatal rat heart following prenatal exposure to ethylene glycol monomethyl ether.
Toraason-M; Stringer-B; Smith-R
Drug Chem Toxicol 1986; 9(1):1-14
The effects of prenatal exposure to ethylene-glycol-monomethyl-ether (109864) (EGME) on heart function in neonatal rats were examined by measuring basal heart ornithine-decarboxylase (ODC) activity and ODC activity after isoproterenol challenge. Pregnant Sprague-Dawley- rats were given 25mg/kg EGME in water by gavage on days seven to 13 or 13 to 19 of gestation. Offspring were sacrificed on day three, nine, 16 or 22. Maternal weight, the number of offspring or the viability of those offspring were not affected by EGME exposure, but there was an increase in the gestation period. ODC levels were similar to controls in rats who had been exposed to EGME on days 13- 19 of gestation. Exposure on days 7-13 of gestation caused significant decreases in ODC activity for both the basal and the isoproterenol challenged groups. ODC activity was stimulated in all isoproterenol groups at all times. The response to isoproterenol was not significantly altered by exposure to EGME. The authors conclude that exposure to EGME at levels which are not necessarily toxic or teratogenic can still disrupt the normal pattern of ODC activity in the heart. Additional functional disturbances were not noted, even under isoproterenol challenge. In order to use changes in ODC activity for the purposes of evaluating risk, dose levels must be used that will provide a range of toxicity so that it can be seen whether ODC activity changes will occur when more or less overt toxicity is also present.
NIOSH-Author; Enzyme-activity; Enzyme-inhibitors; Laboratory-animals; Metabolic-study; Solvents; Cardiovascular-system-disorders; Glycols; Ethers
Drug and Chemical Toxicology