Author/Editor     Saghafi, MM; Pregelj, P; Živin, M
Title     Donepezil inhibits diisopropylfluorophosphate-induced seizures and up-regulation of synaptotagmin 4 mRNA
Type     članek
Source     Folia biol Praha
Vol. and No.     Letnik 56
Publication year     2010
Volume     str. 256-62
Language     eng
Abstract     Reversible acetylcholinesterase inhibitor donepezil displays prophylactic effects against intoxication with irreversible organophosphorous acetylcholinesterase inhibitors. We used behavioural observation of yawning and epileptic seizures, histochemical acetylcholinesterase staining, and in situ hybridization of the immediate early genes, c-fos and synaptotagmin 4 (Syt4) mRNAs in the brain, to evaluate whether donepezil could protect the brain against the effects of the organophosphate anticholinesterase, diisopropylfluorophosphate, in a rat model of intoxication. Diisopropylfluorophosphatetreated animals exhibited frequent yawning, significant inhibition of acetylcholinesterase staining and upregulation of c-fos mRNA, but not the epileptic seizures or significant change of Syt4 mRNA levels. In order to reduce the threshold for the induction of cholinergic seizures, additional groups of rats were pre-treated with LiCl 24 h before the treatment with diisopropylfluorophosphate. These rats exhibited the seizures, a significant inhibition of acetylcholinesterase staining and significant upregulation of c-fos and Syt4 mRNA levels. All the above-mentioned effects of diisopropylfluorophosphate were inhibited by donepezil pre-treatment. Donepezil pre-treatment by itself induced only a comparatively weaker inhibition of acetylcholinesterase staining and infrequent yawning. We conclude that donepezil protects the brain against diisopropylfluorophosphate-induced effects and that Syt4 mRNA upregulation may serve as a novel marker for organophosphate-induced seizures.
Descriptors     SEIZURES
ISOFLUROPHATE
CHOLINESTERASE INHIBITORS
ACETYLCHOLINESTERASE
RNA, MESSENGER
BRAIN
BEHAVIOR, ANIMAL
IN SITU HYBRIDIZATION
OLIGONUCLEOTIDE PROBES
HISTOCYTOCHEMISTRY
RATS, WISTAR