title: Neurophysiological assessment of auditory, peripheral nerve, somatosensory, and visual system functions after developmental exposure to ethanol vapors.
abstract: Ethanol-blended gasoline entered the market in response to demand for domestic renewable energy sources, and may result in increased inhalation of ethanol vapors in combination with other volatile gasoline constituents. It is important to understand potential risks of inhalation of ethanol vapors by themselves, and also as a baseline for evaluating the risks of ethanol combined with a complex mixture of hydrocarbon vapors. Because sensory dysfunction has been reported after developmental exposure to ethanol, we evaluated the effects of developmental exposure to ethanol vapors on neurophysiological measures of sensory function as a component of a larger project evaluating developmental ethanol toxicity. Pregnant Long-Evans rats were exposed to target concentrations 0, 5000, 10,000, or 21,000 ppm ethanol vapors for 6.5h/day over GD9-GD20. Sensory evaluations of male offspring began between PND106 and PND128. Peripheral nerve function (compound action potentials, nerve conduction velocity (NCV)), somatosensory (cortical and cerebellar evoked potentials), auditory (brainstem auditory evoked responses), and visual evoked responses were assessed. Visual function assessment included pattern elicited visual evoked potentials (VEPs), VEP contrast sensitivity, and electroretinograms recorded from dark-adapted (scotopic), light-adapted (photopic) flashes, and UV flicker and green flicker. No consistent concentration-related changes were observed for any of the physiological measures. The results show that gestational exposure to ethanol vapor did not result in detectable changes in peripheral nerve, somatosensory, auditory, or visual function when the offspring were assessed as adults.
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Boyes.william@epa.gov.
authors.forename: William K
authors.initials: WK
authors.lastname: Boyes
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Degn.laura@epa.gov.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Degn
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Martin.Sheppard@epa.gov.
authors.forename: Sheppard A
authors.initials: SA
authors.lastname: Martin
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Lyke.danielle@epa.gov.
authors.forename: Danielle F
authors.initials: DF
authors.lastname: Lyke
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Hamm.charlesw@epa.gov.
authors.forename: Charles W
authors.initials: CW
authors.lastname: Hamm
authors.affiliation: Toxicity Assessment Division, Neurotoxicology Branch, MD B105-04, NHEERL, ORD, U.S. EPA, Research Triangle Park, NC 27711, USA. Electronic address: Herr.david@epa.gov.
authors.forename: David W
authors.initials: DW
authors.lastname: Herr
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000187:drug effects / Q000196:embryology / Q000254:growth & development; D058256:Brain Waves / Q000187:drug effects* / Q000502:physiology; D002492:Central Nervous System Depressants / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000633:toxicity*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000187:drug effects; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects; D005074:Evoked Potentials, Visual / Q000187:drug effects; D005260:Female; D008297:Male; D009431:Neural Conduction / Q000187:drug effects*; D010525:Peripheral Nerves / Q000187:drug effects / Q000196:embryology / Q000254:growth & development; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced / Q000503:physiopathology; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000187:drug effects
chemical_list: D002492:Central Nervous System Depressants; D000431:Ethanol
keywords: Developmental neurotoxicity; Electroretinogram; Ethanol vapor; Nerve conduction velocity; Sensory evoked potentials