title: Neonatal exposure to whole body ionizing radiation induces adult neurobehavioural defects: Critical period, dose--response effects and strain and sex comparison.
abstract: Development of the brain includes periods which can be critical for its normal maturation. The present study investigates specifically vulnerable peri-/postnatal periods in mice which are essential for understanding the etiology behind radiation induced neurotoxicity and functional defects, including evaluation of neurotoxicity between sexes or commonly used laboratory mouse strains following low/moderate doses of ionizing radiation (IR). Male Naval Medical Research Institute (NMRI) mice, whole body irradiated to a single 500 mGy IR dose, on postnatal day (PND) 3 or PND 10 showed an altered adult spontaneous behaviour and impaired habituation capacity, whereas irradiation on PND 19 did not have any impact on the studied variables. Both NMRI and C57bl/6 male and female mice showed an altered adult spontaneous behaviour and impaired habituation following a single whole body irradiation of 500 or 1000 mGy, but not after 20 or 100 mGy, on PND 10. The present study shows that exposure to low/moderate doses of IR during critical life stages might be involved in the induction of neurological/neurodegenerative disorder/disease. A specifically vulnerable period for radiation induced neurotoxicity seems to be around PND 3-10 in mice. Further studies are needed to investigate mechanisms involved in induction of developmental neurotoxicity following low-dose irradiation.
authors.affiliation: Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-75236 Uppsala, Sweden. Electronic address: per.eriksson@ebc.uu.se.
authors.forename: Per
authors.initials: P
authors.lastname: Eriksson
authors.affiliation: Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-75236 Uppsala, Sweden.
authors.forename: Sonja
authors.initials: S
authors.lastname: Buratovic
authors.affiliation: Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-75236 Uppsala, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Fredriksson
authors.affiliation: Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Stenerlöw
authors.affiliation: Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
authors.forename: Synnöve
authors.initials: S
authors.lastname: Sundell-Bergman
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001526:Behavioral Symptoms / Q000209:etiology*; D004307:Dose-Response Relationship, Radiation; D005106:Exploratory Behavior / Q000528:radiation effects; D005260:Female; D008124:Locomotion / Q000528:radiation effects; D008297:Male; D051379:Mice; D065886:Neurodevelopmental Disorders / Q000209:etiology*; D011247:Pregnancy; D011839:Radiation, Ionizing; D012727:Sex Characteristics; D013045:Species Specificity; D018709:Statistics, Nonparametric; D013997:Time Factors; D014916:Whole-Body Irradiation / Q000009:adverse effects*
keywords: Brain development; Low-dose radiation; Neonatal; Sex difference; Strain difference; behaviour