Time-Course Effects of GA, GB, GD, GF and VX on Spinal Cord Cholinesterase and Acetylcholine Levels in Six Discrete Areas of the Rat Brain

摘要

The time-course changes of spinal cord cholinesterase (ChE) and acetylcholine (ACh) levels in six discrete regions of the rat brain were studied and compared. Rats were injected subcutaneously with a 0.9 LD50 dose of GA, GE, GD, GF or VX. They were observed for symptoms of intoxication and head-focused microwave irradiated at 10 time points ranging from 5 minutes to 24 hours after compound administration. Brain tissue samples were homogenized and ACh analyzed using a high pressure liquid chromatographic (HPLC) method. Spinal cords were analyzed at each time point for degree of ChE inhibition. Results indicate that all five compounds produced observable signs of intoxication within 10 minutes after injection. Each compound inhibits ChE, resulting in increased levels of ACh within 10 minutes after administration, and the cortical and hippocampal areas were most sensitive to the effects of these compounds. Observable signs of intoxication, depression of spinal ChE activity and elevation of brain levels of ACh were similar for all of the compounds.