Progressive behavioral changes during the maturation of rats with early radiation-induced hypoplasia of fascia dentata granule cells

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:7018459

Mickley, G A; Ferguson, J L; Mulvihill, M A; Nemeth, T J

Localized exposure of the neonatal rat brain to x rays produces neuronal hypoplasia specific to the granule cell layer of the hippocampal dentate gyrus. This brain damage causes locomotor hyperactivity, slowed acquisition of passive avoidance tasks and long bouts of spontaneous turning (without reversals) in a bowl apparatus. The authors report here how these behavioral deficits change as a function of subject aging and behavioral test replications. Portions of the neonatal rat cerebral hemispheres were X-irradiated in order to selectively damage the granule cells of the dentate gyrus. Rats between the ages of 71-462 days were tested 3 separate times on each of the following 3 behavioral tests: (1) spontaneous locomotion, (2) passive avoidance acquisition, and (3) spontaneous circling in a large plastic hemisphere. Rats with radiation-induced damage to the fascia dentata exhibited long bouts of slow turns without reversals. Once they began, irradiated subjects perseverated in turning to an extent significantly greater than sham-irradiated control subjects. The hyperactivity of the irradiated animals decreased significantly as they matured. These data suggest that radiation-induced damage to the fascia dentata produces task-dependent behavioral deficits that change as a function of subject age and/or behavioral testing.

• Research Organization: Armed Forces Radiobiology Research Inst., Bethesda, MD (USA)
• OSTI ID: 7018459
• Report Number(s): AD-A-214236/2/XAB; AFRRI-SR--89-33
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AGE GROUPS
ANIMAL CELLS
AVOIDANCE
BEHAVIOR
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
CEREBRUM
CHILDREN
CONNECTIVE TISSUE CELLS
ELECTROMAGNETIC RADIATION
HIPPOCAMPUS
INFANTS
INJURIES
IONIZING RADIATIONS
IRRADIATION
MATURATION
NERVOUS SYSTEM
ORGANS
RADIATION EFFECTS
RADIATION INJURIES
RADIATIONS
SOMATIC CELLS
X RADIATION