Mechanism of RDX-induced seizures in rats (Toxicology Study No. 87-XE-0BT9-09)

Williams, LR; Bannon, DI

HERO ID

630143

Reference Type

Technical Report

Year

2009

Language

English

HERO ID 630143
Year 2009
Title Mechanism of RDX-induced seizures in rats (Toxicology Study No. 87-XE-0BT9-09)
Authors Williams, LR; Bannon, DI
Publisher Text U.S. Army Center for Health Promotion and Preventive Medicine, Health Effects Research Program
City Aberdeen Proving Ground, MD
Abstract RDX is found in soil and ground water in and surrounding training ranges, creating potential hazards to human health. Oral RDX over-exposure causes seizure in rats and humans, the mechanism of which is unknown. In this study rats were dosed orally at 75 mg/kg RDX to induce seizure. The brain concentration of RDX was determined in samples taken from rats euthanized at the time of seizure onset: brain acetylchohnesterase was also measured. Also, RDX was screened for affinity to a library of brain receptors to determine if RDX affected any seizure-related targets. Brain concentrations of RDX were greater than 8 microg/g wet wt. in the animals that seized. RDX was found to bind exclusively to the convulsant site on the GABAa receptor with an IC 50 of 22 microM. The mechanism of RDX-induced seizure is likely due to dis-inhibition of excitatory neurons by blockage of the GABA-mediated inhibitory chloride current. This valuable information contributes mode of action insights that can be used in the physiologically-based pharmacokinetic modeling to extrapolate rat data to human.
Report Number ADA511072. USACHPPM-TSN-87-XE-0BT9-09
Ntis Number ADA511072
Url http://www.dtic.mil/docs/citations/ADA511072
Is Certified Translation No
Dupe Override No
Number Of Pages 26
Is Public Yes
Language Text English
Keyword rats; rdx; enzymes; brain damage; nerve cells; public health; receptor sites(physiology); ground water; humans; hazards; soils