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Updated: Jul 15, 2026

A Plate-Based Assay for the Measurement of Endogenous Monoamine Release in Acute Brain Slices
Published on: August 11, 2021
Effects of imipramine on extracellular serotonin and noradrenaline concentrations in ACTH-treated rats
Yoshihisa Kitamura1, Kozue Akiyama, Shinji Hashimoto
1Department of Pharmaceutical Care and Health Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan. ykita@pheasant.pharm.okayama-u.ac.jp
Abstract:
We investigated the effect of imipramine on extracellular serotonin (5-HT) and noradrenaline concentrations in the medial prefrontal cortex of rats treated with adrenocorticotropic hormone (ACTH) for 14 days using in vivo microdialysis. Chronic ACTH treatment did not affect basal extracellular 5-HT and noradrenaline concentrations compared with chronic saline treatment. Acute imipramine treatment plus chronic ACTH treatment significantly increased extracellular 5-HT concentrations, compared with imipramine treatment alone. 8-hydroxy-2-di-n-propylamino tetralin (8-OH-DPAT), a 5-HT1A receptors full agonist, caused a significant decrease in extracellular 5-HT concentrations. However, its inhibitory effect was attenuated by the treatment with ACTH for 14 days. These findings suggest that chronic treatment with ACTH enhances the increasing effect release of 5-HT by imipramine through the desensitization of somatodendritic 5-HT1A autoreceptors.
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