Accession Number : ADA139909

Title :   Nonlinear Performance Interaction upon Exposure to Anticholinesterase and Ionizing Radiation.

Descriptive Note : Final rept. Jan-Apr 83,

Corporate Author : SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TX

Personal Author(s) : Wheeler,T G ; Cordts,R E

PDF Url : ADA139909

Report Date : Feb 1984

Pagination or Media Count : 17

Abstract : Data on anticholinesterase- and radiation-induced performance deficits suggest that combined exposures would prove more detrimental than either insult presented alone. This hypothesis was tested across radiation (0-7 Gy) and physostigmine (0-0.1 mg/kg) exposure levels and using a rodent rotarod task. The rat was trained to walk on a rotating rod which accelerated from 5 to 45 rpm at 1 rpm/s. The measure of motor performance was the length of time that the animal could stay on the rod. Physostigmine was injected and performance measured at three postirradiation times (45 min and days 4 and 8). The physostigmine-only effect was dose dependent and consistent across test times. The radiation-only effect was also dose dependent, but the performance deficit was also postirradiation-time dependent. The effect of exposure to both radiation and physostigmine was not additive. At 45 min after irradiation, the combined-treatment groups' deficit was greater than either of the single-treatment groups'. However, by postirradiation day 4, the combined-treatment groups' deficit was no greater than the greatest deficit observed for a single-treatment group. These data are discussed in terms of a possible adaptation mechanism for ionizing radiation as a generalized stressor.

Descriptors :   *Ionizing radiation, *Cholinesterase inhibitors, *Physostigmine, *Radiation effects, Performance tests, Motor reactions, Measurement, Irradiation, Rats

Subject Categories : Radiobiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE