Prenatal dexamethasone augments the sex-selective developmental neurotoxicity of chlorpyrifos: implications for vulnerability after pharmacotherapy for preterm labor.

ABSTRACT: Glucocorticoids are routinely given in preterm labor and are also elevated by maternal stress; organophosphate exposures are virtually ubiquitous, so coexposures to these two agents are pervasive. We administered dexamethasone to pregnant rats on gestational days 17-19 at a standard therapeutic dose (0.2mg/kg); offspring were then given chlorpyrifos on postnatal days 1-4, at a dose (1mg/kg) that produces barely-detectable (<10%) inhibition of brain cholinesterase activity. We evaluated indices for acetylcholine (ACh) synaptic function throughout adolescence, young adulthood and later adulthood, in brain regions possessing the majority of ACh projections and cell bodies; we measured nicotinic ACh receptor binding, hemicholinium-3 binding to the presynaptic choline transporter and choline ac

SUBMITTER: Slotkin TA 

PROVIDER: S-EPMC3669256 | biostudies-literature | 2013 May-Jun

REPOSITORIES: biostudies-literature