Cerebral impact of prenatal irradiation by 131I: an experimental model of clinical neuroradioembryological effects

• Published in: Problemy radiat͡s︡iĭnoï medyt͡s︡yny ta radiobiolohiï Vol. 22; p. 238
• Main Authors: Talko, V V, Loganovsky, K M, Drozd, I P, Tukalenko, Ye V, Loganovska, T K, Nechayev, S Yu, Masiuk, S V, Prokhorova, Ye M
• Format: Journal Article
• Language: English
• Published: Ukraine 01.12.2017
• Subjects: Adult; Animals; Case-Control Studies; Cerebral Cortex - physiopathology; Cerebral Cortex - radiation effects; Chernobyl Nuclear Accident; Cognitive Dysfunction - etiology; Cognitive Dysfunction - physiopathology; Cognitive Dysfunction - psychology; Conditioning, Classical - radiation effects; Embryo, Mammalian - radiation effects; Exploratory Behavior - radiation effects; Female; Humans; Iodine Radioisotopes - administration & dosage; Limbic System - physiopathology; Limbic System - radiation effects; Locomotion - radiation effects; Male; Maternal Exposure - adverse effects; Mental Status and Dementia Tests; Pregnancy; Prenatal Exposure Delayed Effects - physiopathology; Prenatal Exposure Delayed Effects - psychology; Psychomotor Performance - radiation effects; Radiation Exposure - adverse effects; Radiation Injuries, Experimental - physiopathology; Radiation Injuries, Experimental - psychology; Rats; Rats, Wistar; neuroradioembryological effects; social adaptation; innovative approaches; cortical limbic system; Chornobyl catastrophe; cerebral prenatal irradiation; 131I; hippocampal neurogenesis
• ISSN: 2304-8336
• DOI: 10.33145/2304-8336-2017-22-238-269

Human brain in prenatal period is a most vulnerable to ionizing radiation body structure. Unlike atomic bombings or radiological interventions in healthcare leading at most to external irradiation the intensive internal exposure may occur upon nuclear reactor accidents followed by substantial release and fallout of radioactive 131I. The latter can lead to specific neuroradioembryological effects. To create an experimental model of prenatal cerebral radiation effects of 131I in human and to determine the experimental and clinical neuroradioembryological effects.Study object. The neuroradioembryological effects in Vistar rats exposed to 131I in prenatal period. Nervous system status and mental status in 104 persons exposed to ionizing radiation in utero due to the ChNPP accident and the same in 78 not exposed subjects. Experimental i.e. behavioral techniques, including the spontaneous locomotive, exploratory activity and learning ability assessment, clinical i.e. neuropsychiatric, neuro and psychometric, neuropsychological, neurophys iological methods, both with dosimetric and statistical methods were applied. Intrauterine irradiation of Wistar rats by 131I was simulated on a model of one time oral 27.5 kBq radionu clide administration in the mid gestation period (0.72±0.14 Gy fetal thyroid dose), which provides extrapolation of neuroradioembryological effects in rats to that in humans exposed to intrauterine radiation as a result of the Chornobyl catastrophe. Abnormalities in behavioral reactions and decreased output of conditioned reflex reactions identified in the 10 month old rats suggest a deterioration of cerebral cognition in exposed animals. Specific cog nitive deficit featuring a disharmonic intellectual development through the relatively decreased verbal intelligence versus relative increase of nonverbal one is remained in prenatally exposed persons. This can indicate to dysfunc tion of cortical limbic system with especial involvement of a dominant hemisphere hippocampus. Decreased theta band spectral power (4-7 Hz range) of cerebral bioelectrical activity in the left frontotemporal area is suggestive of hippocampal dysfunction mainly in dominant hemisphere of prenatally irradiated persons. Disorders of hippocam pal neurogenesis due to prenatal exposure by radioactive iodine can be a biologic basis here. Innovative approach es in social adaptation, psychoprophylaxis and psychorehabilitation involve the maximum effective application and development of just the most developed psychological and cognitive abilities in survivors.