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Acetylcholinesterase inhibitor ENA-713 protects against ischemia-induced decrease in pre- and postsynaptic cholinergic indices in the gerbil brain following transient ischemia.

K Tanaka·N Ogawa·K Mizukawa·M Asanuma·Y Kondo·S Nishibayashi·A Mori
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Abstract

The effects of pre-treatment with ENA-713, an acetylcholinesterase (AChE) inhibitor, on changes in pre- and postsynaptic cholinergic indices in gerbil brain following transient ischemia were studied at 4 and 14 days after recirculation. In the ischemic group, hippocampal acetylcholine (ACh) level was significantly reduced (to 23% of sham-operated controls) at 4 days post-ischemia, but this reduction was completely prevented by ENA-713 treatment. Choline acetyltransferase (ChAT) and cholinesterase (ChE) activities were not significantly changed at 4 and 14 days post-ischemia. Although the maximum number (Bmax) of muscarinic ACh receptor (mACh-R) binding in the hippocampus was decreased (to 44%) without any change in affinity at 14 days post-ischemia, this decrease was also inhibited by ENA-713 treatment. In addition, histological experiment indicated that ENA-713 inhibited ischemia-induced pyramidal cell loss in the hippocampal CA1 regions. Thus, these findings suggest that ENA-713 has protective, neurotrophic and therapeutic effects on cerebrovascular type dementia due to cerebral ischemia.

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AcetylcholineAnimalsCarbamatesCholinesterase InhibitorsGerbillinaeIschemic Attack, TransientMolecular StructurePhenylcarbamatesReceptors, MuscarinicRivastigmineSynapsesJournal ArticleResearch Support, Non-U.S. Gov't

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K Tanaka, N Ogawa, K Mizukawa, M Asanuma, Y Kondo, S Nishibayashi, A Mori. 1994. Acetylcholinesterase inhibitor ENA-713 protects against ischemia-induced decrease in pre- and postsynaptic cholinergic indices in the gerbil brain following transient ischemia.. https://doi.org/10.1007/bf00966804

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