Emre Uyar, Meral Erdinç, İlker Kelle, Levent Erdinç, Uğur Şeker, Yusuf Nergiz
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引用次数: 0
Abstract
Background: Glutamatergic N-methyl-D-aspartate (NMDA) receptors play vital roles in memory formation. Changes in the activity of these receptors influence memory processes. Ketamine is a noncompetitive NMDA receptor antagonist drug with promising mood-altering and pain-reducing effects in low doses. These effects are believed to be related to altered serotonergic transmission.
Methods: The present study investigated the involvement of the serotonergic system in low-dose ketamine administrations' effects on memory acquisition, consolidation, and retrieval processes. Sixty-four male BALB/c mice were used in this experiment and separated into 8t groups. Mice were treated subchronically with a selective serotonin reuptake inhibitor, fluoxetine, and a serotonin depletion agent, p-chlorophenylalanine (pCPA). A serotonin antagonist, methiothepin, and ketamine were acutely administered 60 minutes before or after the behavioral tests. A passive avoidance (PA) test measured emotional memory acquisition, consolidation, and retrieval processes. Hippocampi malondialdehyde (MDA) levels were analyzed, and histopathological examinations were performed.
Results: Ketamine alone did not significantly affect memory encoding processes in the PA test, while the ketamine-fluoxetine combination disrupted memory consolidation. Fluoxetine negatively affected the memory acquisition process, which was normalized during the consolidation and retrieval trials. Drug applications did not significantly alter hippocampal MDA levels. In all ketamine-applied groups, histopathologic alterations were evident.
Conclusion: Low-dose ketamine administration induces neurodegeneration, and it also impairs memory functions when combined with fluoxetine, indicating increased serotonergic transmission may be involved in the memory-impairing and neurotoxic effects of ketamine.
期刊介绍:
Eurasian Journal of Medicine (Eurasian J Med) is an international, scientific, open access periodical published by independent, unbiased, and triple-blinded peer-review principles. The journal is the official publication of Atatürk University School of Medicine and published triannually in February, June, and October. The publication language of the journal is English. The aim of the Eurasian Journal of Medicine is to publish original research papers of the highest scientific and clinical value in all medical fields. The Eurasian J Med also includes reviews, editorial short notes and letters to the editor that either as a comment related to recently published articles in our journal or as a case report. The target audience of the journal includes researchers, physicians and healthcare professionals who are interested or working in in all medical disciplines.