Headliners: Developmental Neurotoxicity: Drug Used to Arrest Preterm Labor Sensitizes the Brain to Neurotoxicants

Abstract

Vol. 112, No. 10 EnvironewsOpen AccessHeadliners: Developmental Neurotoxicity: Drug Used to Arrest Preterm Labor Sensitizes the Brain to Neurotoxicants Jerry Phelps Jerry Phelps Search for more papers by this author Published:1 July 2004https://doi.org/10.1289/ehp.112-a553AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Rhodes MC, Seidler FJ, Qiao D, Tate CA, Cousins MM, Slotkin TA. 2004. Does pharmacotherapy for preterm labor sensitize the developing brain to environmental neurotoxicants? Cellular and synaptic effects of sequential exposure to terbutaline and chlorpyrifos in neonatal rats. Toxicol Appl Pharmacol 195:203–217.A growing body of evidence suggests that exposure to environmental toxicants in utero or very early after birth can have life-long effects. This phenomenon is referred to as the fetal basis of adult disease. Hypertension, diabetes mellitus, asthma, and cardiovascular diseases are but a few of the illnesses that have been suggested as possible effects from early-life exposures. Recently, NIEHS grantee Theodore A. Slotkin of Duke University Medical Center and his colleagues investigated how separate and combined exposures to terbutaline, a drug used to arrest preterm labor, and to the organophosphate pesticide chlorpyrifos affect several indices of brain cell growth and function.Premature labor occurs in approximately 20% of all U.S. pregnancies, with preterm delivery—a leading cause of neonatal morbidity and mortality—occurring in nearly half these cases. Drugs to arrest preterm labor, particularly terbutaline, are used in as many as 1 million pregnancies annually. Chlorpyrifos, a known developmental neurotoxicant, is used worldwide.Rat pups were given terbutaline on days 2–5 after birth, followed by chlorpyrifos on days 11–14. Neither treatment affected the growth or viability of the young rats; however, both elicited alterations in brain cell differentiation and cholinergic innervation at day 15, persisting into adulthood at day 60. Biomarkers of brain cell number, cell size, and neuritic projections were affected by both agents alone. However, the combined exposure produced more severe effects by both additive and synergistic mechanisms.These findings suggest that terbutaline, like chlorpyrifos, is a developmental neurotoxicant. The authors conclude that the use of terbutaline to prevent preterm labor may be creating a subpopulation that is more sensitive to the adverse neural effects of organophosphate pesticides. Further studies are needed to repeat these findings, but if the results are confirmed, use of these compounds may warrant additional scrutiny. –Jerry PhelpsFigures and TablesFiguresReferencesRelatedDetails Vol. 112, No. 10 July 2004Metrics About Article Metrics Publication History Originally published1 July 2004Published in print1 July 2004 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.