title: Different inhibition of acetylcholinesterase in selected parts of the rat brain following intoxication with VX and Russian VX.
abstract: Differences between acetylcholinesterase (AChE) inhibition in the brain structures following VX and RVX exposure are not known as well as information on the possible correlation of biochemical and histochemical methods detecting AChE activity. Therefore, inhibition of AChE in different brain parts detected by histochemical and biochemical techniques was compared in rats intoxicated with VX and RVX. AChE activities in defined brain regions 30 min after treating rats with VX and Russian VX intramuscularly (1.0 x LD(50)) were determined by using biochemical and histochemical methods. AChE inhibition was less expressed for RVX, in comparison with VX. Frontal cortex and pontomedullar areas containing ncl. reticularis has been found as the most sensitive areas for the action of VX. For RVX, these structures were determined to be frontal cortex, dorsal septum, and hippocampus, respectively. Histochemical and biochemical results were in good correlation (R(xy) = 0.8337). Determination of AChE activity in defined brain structures was a more sensitive parameter for VX or RVX exposure than the determination of AChE activity in the whole-brain homogenate. This activity represents a "mean" of the activities in different structures. Thus, AChE activity is the main parameter investigated in studies searching for target sites following nerve-agent poisoning contributing to better understanding of toxicodynamics of nerve agents.
authors.affiliation: Department of Anatomy, Medical Faculty of Charles University, Hradec Kralove, Czech Republic. hajekp@lfhk.uni.cz
authors.forename: Petr
authors.initials: P
authors.lastname: Hajek
authors.forename: Jiri
authors.initials: J
authors.lastname: Bajgar
authors.forename: Dasa
authors.initials: D
authors.lastname: Slizova
authors.forename: Otakar
authors.initials: O
authors.lastname: Krs
authors.forename: Kamil
authors.initials: K
authors.lastname: Kuca
authors.forename: Lukas
authors.initials: L
authors.lastname: Capek
authors.forename: Josef
authors.initials: J
authors.lastname: Fusek
mesh_terms: D000110:Acetylcholinesterase / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000201:enzymology; D002619:Chemical Warfare Agents / Q000506:poisoning*; D002800:Cholinesterase Inhibitors / Q000506:poisoning*; D005260:Female; D007273:Injections, Intramuscular; D007928:Lethal Dose 50; D009946:Organothiophosphorus Compounds / Q000506:poisoning*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000110:Acetylcholinesterase; D002619:Chemical Warfare Agents; D002800:Cholinesterase Inhibitors; D009946:Organothiophosphorus Compounds; C009680:VX-agent; C451779:S-(N,N-diethylaminoethyl) isobutyl methylphosphothiolate