The benzodiazepine receptor antagonist flumazenil increases acetylcholine release in rat hippocampus
Brain ResearchPublished 1 May 1994
Assunta Impérato, Laura Dazzi, M.Carmen Obinu, Gian Luigi Gessa, Giovanni Biggio
Citations42
SJR quartileQ2
SJR score0.85
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TL;DR
The changes in hippocampal cholinergic function elicited by activation and blockade of benzodiazepine receptors in the medial septum may play a crucial role in the alterations of the cognitive processes eliciting by benzodiazine receptor ligands.
Abstract
The benzodiazepine receptor antagonist flumazenil (2.5-20 mg/kg i.p.) increased acetylcholine (ACh) release by up to 85% in the hippocampus of freely moving rats. In contrast, the benzodiazepine receptor full agonist diazepam (2.5-10 mg/kg i.p.) decreased ACh release up to a maximum of 45% in the same brain area. Injection of flumazenil (10 pmol) or diazepam (10 pmol) into the medial septum increased (95%) or reduced (50%), respectively, ACh release in the hippocampus. The maximum effect produced by those drugs was of the same magnitude as that observed after systemic injection. The changes in hippocampal cholinergic function elicited by activation and blockade of benzodiazepine receptors in the medial septum may thus play a crucial role in the alterations of the cognitive processes elicited by benzodiazepine receptor ligands.
Keywords
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