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Ogasawara J, Matsumoto N, Takeuchi Y, Yamashiro K, Yasui M, Ikegaya Y. Lengthened circadian rhythms in mice with self-controlled ambient light intensity. Sci Rep 2024; 14:7778. [PMID: 38565587 PMCID: PMC10987682 DOI: 10.1038/s41598-024-58415-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 03/28/2024] [Indexed: 04/04/2024] Open
Abstract
Laboratory animals are typically maintained under 12-h light and 12-h dark (12:12 LD) conditions with a daytime light intensity of ~ 200 lx. In this study, we designed an apparatus that allowed mice to self-select the room light intensity by nose poking. We measured the behavioral rhythms of the mice under this self-controlled light regimen. The mice quickly learned the relationship between their nose pokes and the resulting changes in the light intensity. Under these conditions, the mice exhibited free-running circadian behavior with a period of 24.5 ± 0.4 h. This circadian period was ~ 1 h longer than that of the same strain of mice when they were kept in constant darkness (DD) after 12:12 LD entrainment, and the lengthened period lasted for at least 30 days. The rhythm of the light intensity controlled by the mice also exhibited a similar period, but the phase of the illuminance rhythm preceded the phase of the locomotor activity rhythm. Mice that did not have access to the light controller were also entrained to the illuminance cycle produced by the mice that did have access to the light controller, but with a slightly delayed phase. The rhythm was likely controlled by the canonical circadian clock because mice with tau mutations in the circadian clock gene CSNK1E exhibited short periods of circadian rhythm under the same conditions. These results indicate that the free-running period of mice in the wild may differ from what they exhibit if they are attuned by forced light cycles in laboratories because mice in their natural habitats can self-control their exposure to ambient light, similar to our experimental conditions.
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Affiliation(s)
- Jun Ogasawara
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, 160-8582, Japan
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Nobuyoshi Matsumoto
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for AI and Beyond, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Yuki Takeuchi
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kotaro Yamashiro
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Masato Yasui
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, 160-8582, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
- Institute for AI and Beyond, The University of Tokyo, Tokyo, 113-0033, Japan.
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita City, Osaka, 565-0871, Japan.
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Shen Y, Huai B, Wang X, Chen M, Shen X, Han M, Su F, Xin T. Automatic sleep-wake classification and Parkinson's disease recognition using multifeature fusion with support vector machine. CNS Neurosci Ther 2024; 30:e14708. [PMID: 38600857 PMCID: PMC11007385 DOI: 10.1111/cns.14708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 01/29/2024] [Accepted: 02/12/2024] [Indexed: 04/12/2024] Open
Abstract
AIMS Sleep disturbance is a prevalent nonmotor symptom of Parkinson's disease (PD), however, assessing sleep conditions is always time-consuming and labor-intensive. In this study, we performed an automatic sleep-wake state classification and early diagnosis of PD by analyzing the electrocorticography (ECoG) and electromyogram (EMG) signals of both normal and PD rats. METHODS The study utilized ECoG power, EMG amplitude, and corticomuscular coherence values extracted from normal and PD rats to construct sleep-wake scoring models based on the support vector machine algorithm. Subsequently, we incorporated feature values that could act as diagnostic markers for PD and then retrained the models, which could encompass the identification of vigilance states and the diagnosis of PD. RESULTS Features extracted from occipital ECoG signals were more suitable for constructing sleep-wake scoring models than those from frontal ECoG (average Cohen's kappa: 0.73 vs. 0.71). Additionally, after retraining, the new models demonstrated increased sensitivity to PD and accurately determined the sleep-wake states of rats (average Cohen's kappa: 0.79). CONCLUSION This study accomplished the precise detection of substantia nigra lesions and the monitoring of sleep-wake states. The integration of circadian rhythm monitoring and disease state assessment has the potential to improve the efficacy of therapeutic strategies considerably.
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Affiliation(s)
- Yin Shen
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Medical Science and Technology Innovation CenterShandong First Medical University and Shandong Academy of Medical SciencesJinanShandongP. R. China
| | - Baogeng Huai
- First Clinical Medical College, Shandong University of Traditional Chinese MedicineJinanP. R. China
| | - Xiaofeng Wang
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Medical Science and Technology Innovation CenterShandong First Medical University and Shandong Academy of Medical SciencesJinanShandongP. R. China
| | - Min Chen
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Department of RadiologyShandong First Medical University & Shandong Academy of Medical SciencesTaianP. R. China
| | - Xiaoyue Shen
- First Clinical Medical College, Shandong University of Traditional Chinese MedicineJinanP. R. China
| | - Min Han
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Medical Science and Technology Innovation CenterShandong First Medical University and Shandong Academy of Medical SciencesJinanShandongP. R. China
| | - Fei Su
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Department of RadiologyShandong First Medical University & Shandong Academy of Medical SciencesTaianP. R. China
| | - Tao Xin
- Department of NeurosurgeryThe First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan HospitalJinanShandongP. R. China
- Medical Science and Technology Innovation CenterShandong First Medical University and Shandong Academy of Medical SciencesJinanShandongP. R. China
- Institute of Brain Science and Brain‐inspired Research, Shandong First Medical University & Shandong Academy of Medical SciencesJinanShandongP. R. China
- Shandong Institute of Brain Science and Brain‐inspired ResearchJinanShandongP. R. China
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Kawamura M, Yoshimoto A, Ikegaya Y, Matsumoto N. Low Atmospheric Oxygen Attenuates Alpha Oscillations in the Primary Motor Cortex of Awake Rats. Biol Pharm Bull 2024; 47:462-468. [PMID: 38382999 DOI: 10.1248/bpb.b23-00863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Oxygen is pivotal for survival of animals. Their cellular activity and cognitive behavior are impaired when atmospheric oxygen is insufficient, called hypoxia. However, concurrent effects of hypoxia on physiological signals are poorly understood. To address this question, we simultaneously recorded local field potentials in the primary motor cortex, primary somatosensory, and anterior cingulate cortex, electrocardiograms, electroolfactograms, and electromyograms of rats under acute hypoxic conditions (i.e., 5.0% O2). Exposure to acute hypoxia significantly attenuated alpha oscillations alone in the primary motor cortex, while we failed to find any effects of acute hypoxia on the oscillatory power in the somatosensory cortex or anterior cingulate cortex. These area- and frequency-specific effects by hypoxia may be accounted for by neural innervation from the brainstem to each cortical area via thalamic relay nuclei. Moreover, we found that heart rate and respiratory rate were increased during acute hypoxia and high heart rate was maintained even after the oxygen level returned to the baseline. Altogether, our study characterizes a systemic effect of atmospheric hypoxia on neural and peripheral signals from physiological viewpoints, leading to bridging a gap between cellular and behavioral levels.
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Affiliation(s)
- Masashi Kawamura
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
| | - Airi Yoshimoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
- Institute for AI and Beyond, The University of Tokyo
- Center for Information and Neural Networks, National Institute of Information and Communications Technology
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
- Institute for AI and Beyond, The University of Tokyo
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Kudara M, Kato-Ishikura E, Ikegaya Y, Matsumoto N. Ramelteon administration enhances novel object recognition and spatial working memory in mice. J Pharmacol Sci 2023; 152:128-135. [PMID: 37169477 DOI: 10.1016/j.jphs.2023.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 03/17/2023] [Accepted: 04/10/2023] [Indexed: 05/13/2023] Open
Abstract
Ramelteon is used to ameliorate sleep disorders that negatively affect memory performance; however, it remains unknown whether ramelteon strengthens neutral memories, which do not involve reward or punishment. To address this, we monitored behavior of mice treated with vehicle/ramelteon while they performed a novel object recognition task and a spontaneous alternation task. Object memory performance in the novel object recognition task was improved only if ramelteon was injected before training, suggesting that ramelteon specifically enhances the acquisition of object recognition memory. Ramelteon also enhanced spatial working memory in the spontaneous alternation task. Altogether, acute ramelteon treatment enhances memory in quasi-natural contexts.
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Affiliation(s)
- Mikuru Kudara
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Eriko Kato-Ishikura
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo 113-0033, Japan; Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita City, Osaka, 565-0871, Japan
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo 113-0033, Japan.
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Qi X, Tang Z, Shao X, Wang Z, Li M, Zhang X, He L, Wang J, Yu X. Ramelteon improves blood-brain barrier of focal cerebral ischemia rats to prevent post-stroke depression via upregulating occludin. Behav Brain Res 2023; 449:114472. [PMID: 37146721 DOI: 10.1016/j.bbr.2023.114472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 03/13/2023] [Accepted: 03/20/2023] [Indexed: 05/07/2023]
Abstract
Post-stroke depression (PSD) negatively affects the prognosis of post-stroke animals. Ramelteon has neuroprotection for chronic ischemia animals, but the effect and the biological mechanism of it on PSD is still unclear. This study explored the effects of ramelteon with prophylactic administration on blood-brain barrier in rats with middle cerebral artery occlusion (MCAO) and the oxygen-glucose deprivation/reperfusion (OGD/R) bEnd.3 cells and found that ramelteon pretreatment improved the depressive-like behaviors and decreased infarct area in MCAO rats. Also, this study found ramelteon pretreatment improved viability and inhibited permeability in OGD/R cells. In addition, this study found that MCP-1, TNF-α, and IL-1 levels were raised in the MCAO rats and that occludin protein and mRNA levels were decreased in the MCAO and the OGD/R models, while the Egr-1 level was up-regulated. All of these were antagonized by ramelteon pretreatment. In addition, overexpression of Egr-1 could reverse the effect of 100nM ramelteon pretreatment on FITC and occludin levels in OGD/R cells. In short, this study has demonstrated that the protective effect on PSD of ramelteon pretreatment on MCAO rats is related to the development of BBB permeability and that ramelteon regulates occludin to protect the BBB by inhibiting Egr-1.
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Affiliation(s)
- Xuchen Qi
- Department of Neurosurgery, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ziqi Tang
- Department of Psychology, New York University, New York, The United States
| | - Xian Shao
- Medical Research Center, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China
| | - Zhaowei Wang
- Department of Neurology, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China
| | - Mengyun Li
- Medical Research Center, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China
| | - Xiaobing Zhang
- Department of Neurosurgery, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China
| | - Lingyan He
- Department of Traditional Chinese Medicine, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China.
| | - Jianli Wang
- Department of Neurosurgery, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China.
| | - Xuebin Yu
- Department of Neurosurgery, Shaoxing People's Hospital, Zhejiang University Shaoxing Hospital, Shaoxing, China.
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Wang Y, Li M, Li W, Xiao L, Huo X, Ding J, Sun T. Is the insula linked to sleep? A systematic review and narrative synthesis. Heliyon 2022; 8:e11406. [DOI: 10.1016/j.heliyon.2022.e11406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/12/2022] [Accepted: 10/31/2022] [Indexed: 11/08/2022] Open
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Saré RM, Lemons A, Smith CB. Effects of Treatment With Hypnotics on Reduced Sleep Duration and Behavior Abnormalities in a Mouse Model of Fragile X Syndrome. Front Neurosci 2022; 16:811528. [PMID: 35720683 PMCID: PMC9202518 DOI: 10.3389/fnins.2022.811528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 05/10/2022] [Indexed: 11/28/2022] Open
Abstract
Many patients with fragile X syndrome (FXS) have sleep disturbances, and Fmr1 knockout (KO) mice (a model of FXS) have reduced sleep duration compared to wild type (WT). Sleep is important for brain development, and chronic sleep restriction during development has long-lasting behavioral effects in WT mice. We hypothesized that the sleep abnormalities in FXS may contribute to behavioral impairments and that increasing sleep duration might improve behavior. We treated adult male Fmr1 KO and WT mice subacutely with three different classes of hypnotics (DORA-22, ramelteon, and zolpidem) and caffeine, a methylxanthine stimulant, and we tested the effects of treatments on sleep duration and behavior. Behavior tests included activity response to a novel environment, anxiety-like behavior, and social behavior. As expected, all hypnotics increased, and caffeine decreased sleep duration in the circadian phase in which drugs were administered. Caffeine and DORA-22 treatment significantly reduced activity in the open field regardless of genotype. Other effects were not as apparent.
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Shibata Y, Yoshimoto A, Yamashiro K, Ikegaya Y, Matsumoto N. Delayed reinforcement hinders subsequent extinction. Biochem Biophys Res Commun 2022; 591:20-25. [PMID: 34995981 DOI: 10.1016/j.bbrc.2021.12.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/26/2021] [Indexed: 11/23/2022]
Abstract
In operant conditioning, animals associate their own behavior with a reinforcer, and the probability of the behavioral responses is increased. This form of learning is called reinforcement. In contrast, when the previously reinforced responses are no longer paired with a reinforcer, these responses are eventually extinguished. The effectiveness of reinforcement depends primarily on time intervals between reinforcers and responses, but it is not fully understood how the intervals affect subsequent extinction. To address this question, we performed electrical stimulation of the rat medial forebrain bundle (MFB), a part of the brain reward system, and an operant task in which the MFB was electrically stimulated 0.1 s (immediate condition) or 1 s (delayed condition) after the rat's nose was poked. During the first half of the task period (a reinforcement period), nose pokes were associated with MFB stimulation. In contrast, during the second half (an extinction period), we did not stimulate the MFB irrespective of nose pokes. We found that rats exhibited increased nose-poke behaviors during the reinforcement period under both conditions, whereas during the extinction period, nose pokes were more persistent in the delayed condition than in the immediate condition. The persistent responses in the extinction period were independent of responses in the reinforcement period. Therefore, reinforcement and extinction are driven by independent neural mechanisms.
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Affiliation(s)
- Yusuke Shibata
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Airi Yoshimoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Kotaro Yamashiro
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo, 113-0033, Japan; Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita City, Osaka, 565-0871, Japan
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo, 113-0033, Japan.
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Özgöçmen M, Aşcı H, Doğan HK, İlhan İ, Pekgöz Ş, Mustafaoğlu A. A study on Wistar Albino rats: investigating protective role of ramelteon on liver damage caused by methotrexate. Drug Chem Toxicol 2021; 45:2678-2685. [PMID: 34632892 DOI: 10.1080/01480545.2021.1982623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Methotrexate is an important immunosuppressive and antineoplastic drug and is widely used for treatment. However, hepatotoxicity is one of the major adverse effects of methotrexate. In this study, it was aimed to investigate whether ramelteon has a possible protective effect on hepatotoxicity induced by methotrexate. Thirty-two Wistar albino rats were equally divided into four groups: control, methotrexate, methotrexate + ramelteon, and ramelteon. Following a single dose of 20 mg/kg, methotrexate (i.p.), either saline or ramelteon 10 mg/kg (orally) was administered for 7 days. After treatment, animals were sacrificed, and histopathological analyses were evaluated with Hematoxylin-eosin (H-E), immunohistological analyses were evaluated with Interleukın-1 Beta (IL-1β) and Caspase 3 (CAS-3), biochemical analyzes were evaluated with Total Oxidant Status (TOS), Total antioxidants status (TAS), Oxidative Stress Index (OSI), aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities, at last genetical analyses were evaluated with Sirtuin-1 (SIRT-1) - P53 gene expressions. In the control and ramelteon groups, normal histological structures were observed, while histopathological findings were observed in the methotrexate group. Increasing levels of IL-1β staining, CAS-3 staining, p53 gene expression, TOS, OSI, AST and ALT were observed in methotrexate group while were observed decreasing levels of TAS and SIRT-1 gene expression (p < 0.05). However, ramelteon reduced the increased findings in methotrexate-induced hepatotoxicity (p < 0.05). The results of the present study showed that ramelteon protects against methotrexate induced hepatotoxicity in rats via SIRT-1 signaling by histological, immunohistological, biochemical and genetical analyses.
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Affiliation(s)
- Meltem Özgöçmen
- Department of Histology and Embryology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Halil Aşcı
- Department of Pharmacology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Hatice Kübra Doğan
- Department of Bioengineering, Institute of Science, Suleyman Demirel University, Isparta, Turkey
| | - İlter İlhan
- Department of Medical Biochemistry, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Şakir Pekgöz
- Department of Pathology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
| | - Ali Mustafaoğlu
- Department of Histology and Embryology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey
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Abstract
Sleep curtailment negatively affects cardiac activities and thus should be ameliorated by pharmacological methods. One of the therapeutic targets is melatonin receptors, which tune circadian rhythms. Ramelteon, a melatonin MT1/MT2 receptor agonist, has recently been developed to modulate sleep-wake rhythms. To date, the sleep-promoting effect of ramelteon has been widely delineated, but whether ramelteon treatment physiologically influences cardiac function is not well understood. To address this question, we recorded electrocardiograms, electromyograms, and electrocorticograms in the frontal cortex and the olfactory bulb of unrestrained rats treated with either ramelteon or vehicle. We detected vigilance states based on physiological measurements and analyzed cardiac and muscular activities. We found that during non-rapid eye movement (non-REM) sleep, heartrate variability was maintained by ramelteon treatment. Analysis of the electromyograms confirmed that neither microarousal during non-REM sleep nor the occupancy of phasic periods during REM sleep was altered by ramelteon. Our results indicate that ramelteon has a remedial effect on cardiac activity by keeping the heartrate variability and may reduce cardiac dysfunction during sleep.
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Affiliation(s)
- Airi Yoshimoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
| | - Kotaro Yamashiro
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
- Institute for AI and Beyond, The University of Tokyo
- Center for Information and Neural Networks, National Institute of Information and Communications Technology
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