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Hartsock MJ, Brennan NA, Spencer RL. Circadian Rhythms in Fear Extinction Recall Depend on the Time of Day of Extinction Recall, Not the Time of Day of Extinction Learning. J Biol Rhythms 2023; 38:109-115. [PMID: 36281735 DOI: 10.1177/07487304221128161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The recall of conditioned fear extinction exhibits a circadian rhythm in humans and rodents, with optimal extinction recall occurring during the early active phase. However, it remains unclear whether this rhythm depends on the circadian modulation of mechanisms supporting memory consolidation versus memory maintenance and retrieval. Here, adult male rats underwent conditioned fear extinction at one of four times throughout the day and then, starting 24 h after extinction, were repeatedly tested for extinction recall over the next 24 h. Rats undergoing extinction learning during the early active phase tended toward accelerated extinction learning compared with rats in other groups, pointing to rhythms in mechanisms that support extinction memory encoding. The next day, the strength of extinction recall followed a 24-h cycle that depended not on the time of day of extinction learning but, instead, on the time of day of extinction recall. This latter finding indicates a rhythm in mechanisms supporting extinction memory maintenance and/or retrieval. Subsequent testing for fear relapse in the conditioning context suggested reduced fear in rats tested during the early active phase. These results lay the groundwork for mechanistic investigations of circadian rhythms in fear extinction memory.
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Affiliation(s)
- Matthew J Hartsock
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado
| | - Nicholas A Brennan
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado
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2
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Ortinski PI, Reissner KJ, Turner J, Anderson TA, Scimemi A. Control of complex behavior by astrocytes and microglia. Neurosci Biobehav Rev 2022; 137:104651. [PMID: 35367512 DOI: 10.1016/j.neubiorev.2022.104651] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/28/2022] [Accepted: 03/21/2022] [Indexed: 02/07/2023]
Abstract
Evidence that glial cells influence behavior has been gaining a steady foothold in scientific literature. Out of the five main subtypes of glial cells in the brain, astrocytes and microglia have received an outsized share of attention with regard to shaping a wide spectrum of behavioral phenomena and there is growing appreciation that the signals intrinsic to these cells as well as their interactions with surrounding neurons reflect behavioral history in a brain region-specific manner. Considerable regional diversity of glial cell phenotypes is beginning to be recognized and may contribute to behavioral outcomes arising from circuit-specific computations within and across discrete brain nuclei. Here, we summarize current knowledge on the impact of astrocyte and microglia activity on behavioral outcomes, with a specific focus on brain areas relevant to higher cognitive control, reward-seeking, and circadian regulation.
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Affiliation(s)
- P I Ortinski
- Department of Neuroscience, University of Kentucky, USA
| | - K J Reissner
- Department of Psychology and Neuroscience, University of North Carolina Chapel Hill, USA
| | - J Turner
- Department of Pharmaceutical Sciences, University of Kentucky, USA
| | - T A Anderson
- Department of Neuroscience, University of Kentucky, USA
| | - A Scimemi
- Department of Biology, State University of New York at Albany, USA
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Hartsock MJ, Spencer RL. Memory and the circadian system: Identifying candidate mechanisms by which local clocks in the brain may regulate synaptic plasticity. Neurosci Biobehav Rev 2020; 118:134-162. [PMID: 32712278 DOI: 10.1016/j.neubiorev.2020.07.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/11/2022]
Abstract
The circadian system is an endogenous biological network responsible for coordinating near-24-h cycles in behavior and physiology with daily timing cues from the external environment. In this review, we explore how the circadian system regulates memory formation, retention, and recall. Circadian rhythms in these memory processes may arise through several endogenous pathways, and recent work highlights the importance of genetic timekeepers found locally within tissues, called local clocks. We evaluate the circadian memory literature for evidence of local clock involvement in memory, identifying potential nodes for direct interactions between local clock components and mechanisms of synaptic plasticity. Our discussion illustrates how local clocks may pervasively modulate neuronal plastic capacity, a phenomenon that we designate here as circadian metaplasticity. We suggest that this function of local clocks supports the temporal optimization of memory processes, illuminating the potential for circadian therapeutic strategies in the prevention and treatment of memory impairment.
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Affiliation(s)
- Matthew J Hartsock
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
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Paul JR, Davis JA, Goode LK, Becker BK, Fusilier A, Meador-Woodruff A, Gamble KL. Circadian regulation of membrane physiology in neural oscillators throughout the brain. Eur J Neurosci 2019; 51:109-138. [PMID: 30633846 DOI: 10.1111/ejn.14343] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/19/2018] [Accepted: 12/21/2018] [Indexed: 12/21/2022]
Abstract
Twenty-four-hour rhythmicity in physiology and behavior are driven by changes in neurophysiological activity that vary across the light-dark and rest-activity cycle. Although this neural code is most prominent in neurons of the primary circadian pacemaker in the suprachiasmatic nucleus (SCN) of the hypothalamus, there are many other regions in the brain where region-specific function and behavioral rhythmicity may be encoded by changes in electrical properties of those neurons. In this review, we explore the existing evidence for molecular clocks and/or neurophysiological rhythms (i.e., 24 hr) in brain regions outside the SCN. In addition, we highlight the brain regions that are ripe for future investigation into the critical role of circadian rhythmicity for local oscillators. For example, the cerebellum expresses rhythmicity in over 2,000 gene transcripts, and yet we know very little about how circadian regulation drives 24-hr changes in the neural coding responsible for motor coordination. Finally, we conclude with a discussion of how our understanding of circadian regulation of electrical properties may yield insight into disease mechanisms which may lead to novel chronotherapeutic strategies in the future.
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Affiliation(s)
- Jodi R Paul
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jennifer A Davis
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Lacy K Goode
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Bryan K Becker
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Allison Fusilier
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Aidan Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Karen L Gamble
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama
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5
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Recording Field Potentials and Synaptic Plasticity From Freely Behaving Rodents. HANDBOOK OF BEHAVIORAL NEUROSCIENCE 2018. [DOI: 10.1016/b978-0-12-812028-6.00001-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Gonzalez J, Villarreal DM, Morales IS, Derrick BE. Long-term Potentiation at Temporoammonic Path-CA1 Synapses in Freely Moving Rats. Front Neural Circuits 2016; 10:2. [PMID: 26903815 PMCID: PMC4748048 DOI: 10.3389/fncir.2016.00002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 01/12/2016] [Indexed: 11/23/2022] Open
Abstract
Hippocampal area CA1 receives direct entorhinal layer III input via the temporoammonic path (TAP) and recent studies implicate TAP-CA1 synapses are important for some aspects of hippocampal memory function. Nonetheless, as few studies have examined TAP-CA1 synaptic plasticity in vivo, the induction and longevity of TAP-CA1 long-term potentiation (LTP) has not been fully characterized. We analyzed CA1 responses following stimulation of the medial aspect of the angular bundle and investigated LTP at medial temporoammonic path (mTAP)-CA1 synapses in freely moving rats. We demonstrate monosynaptic mTAP-CA1 responses can be isolated in vivo as evidenced by observations of independent current sinks in the stratum lacunosum moleculare of both areas CA1 and CA3 following angular bundle stimulation. Contrasting prior indications that TAP input rarely elicits CA1 discharge, we observed mTAP-CA1 responses that appeared to contain putative population spikes in 40% of our behaving animals. Theta burst high frequency stimulation of mTAP afferents resulted in an input specific and N-methyl-D-aspartate (NMDA) receptor-dependent LTP of mTAP-CA1 responses in behaving animals. LTP of mTAP-CA1 responses decayed as a function of two exponential decay curves with time constants (τ) of 2.7 and 148 days to decay 63.2% of maximal LTP. In contrast, mTAP-CA1 population spike potentiation longevity demonstrated a τ of 9.6 days. To our knowledge, these studies provide the first description of mTAP-CA1 LTP longevity in vivo. These data indicate TAP input to area CA1 is a physiologically relevant afferent system that displays robust synaptic plasticity.
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Affiliation(s)
- Jossina Gonzalez
- Department of Biology, University of Texas at San Antonio San Antonio, TX, USA
| | | | - Isaiah S Morales
- Department of Biology, University of Texas at San Antonio San Antonio, TX, USA
| | - Brian E Derrick
- Department of Biology, University of Texas at San AntonioSan Antonio, TX, USA; UTSA Neurosciences Institute, University of Texas at San AntonioSan Antonio, TX, USA
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Smarr BL, Jennings KJ, Driscoll JR, Kriegsfeld LJ. A time to remember: the role of circadian clocks in learning and memory. Behav Neurosci 2014; 128:283-303. [PMID: 24708297 PMCID: PMC4385793 DOI: 10.1037/a0035963] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The circadian system has pronounced influence on learning and memory, manifesting as marked changes in memory acquisition and recall across the day. From a mechanistic perspective, the majority of studies have investigated mammalian hippocampal-dependent learning and memory, as this system is highly tractable. The hippocampus plays a major role in learning and memory, and has the potential to integrate circadian information in many ways, including information from local, independent oscillators, and through circadian modulation of neurogenesis, synaptic remodeling, intracellular cascades, and epigenetic regulation of gene expression. These local processes are combined with input from other oscillatory systems to synergistically augment hippocampal rhythmic function. This overview presents an account of the current state of knowledge on circadian interactions with learning and memory circuitry and provides a framework for those interested in further exploring these interactions.
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Affiliation(s)
- Benjamin L. Smarr
- Department of Psychology, University of California, Berkeley, CA, 94720 USA
| | | | - Joseph R. Driscoll
- The Helen Wills Neuroscience Institute, University of California, Berkeley, CA, 94720 USA
| | - Lance J. Kriegsfeld
- Department of Psychology, University of California, Berkeley, CA, 94720 USA
- The Helen Wills Neuroscience Institute, University of California, Berkeley, CA, 94720 USA
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Rawashdeh O, Jilg A, Jedlicka P, Slawska J, Thomas L, Saade A, Schwarzacher SW, Stehle JH. PERIOD1 coordinates hippocampal rhythms and memory processing with daytime. Hippocampus 2014; 24:712-23. [DOI: 10.1002/hipo.22262] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 01/26/2014] [Accepted: 02/13/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Oliver Rawashdeh
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Antje Jilg
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Peter Jedlicka
- Institute of Clinical Neuroanatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Jolanta Slawska
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Lukas Thomas
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Anastasia Saade
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Stephan W. Schwarzacher
- Institute of Clinical Neuroanatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
| | - Jörg H. Stehle
- Institute of Cellular and Molecular Anatomy, Dr. Senckenbergische Anatomie; Goethe-University; Theodor-Stern-Kai 7 Frankfurt Germany
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Nakatsuka H, Natsume K. Circadian rhythm modulates long-term potentiation induced at CA1 in rat hippocampal slices. Neurosci Res 2014; 80:1-9. [PMID: 24406747 DOI: 10.1016/j.neures.2013.12.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 11/30/2013] [Accepted: 12/25/2013] [Indexed: 11/25/2022]
Abstract
Circadian rhythm affects neuronal plasticity. Consistent with this, some forms of synaptic long-term potentiation (LTP) are modulated by the light/dark cycle (LD cycle). For example, this type of modulation is observed in hippocampal slices. In rodents, which are nocturnal, LTP is usually facilitated in the dark phase, but the rat hippocampal CA1 is an exception. The reason why LTP in the dark phase is suppressed in CA1 remains unknown. Previously, LTP was induced with high-frequency stimulation. In this study, we found that in the dark phase, theta-burst stimulation-induced LTP is indeed facilitated in CA1, similar to other regions in the rodent brain. Population excitatory postsynaptic potentials (pEPSP)-LTP and population spikes (PS)-LTP were recorded at CA1. The magnitude of PS-LTP in dark-phase slices was significantly larger than in light-phase slices, while that of pEPSP-LTP was unchanged. Using antidromic-orthodromic stimulation, we found that recurrent inhibition is suppressed in the dark phase. Local gabazine-application to stratum pyramidale in light-phase slices mimicked this disinhibition and facilitated LTP in dark-phase slices. These results suggest that the disinhibition of a GABAA recurrent inhibitory network can be induced in the dark phase, thereby facilitating LTP.
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Affiliation(s)
- Hiroki Nakatsuka
- Department of Brain Science and Engineering, Graduate School of Life Science and Systems Engineering, Kyusyu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyusyu, Fukuoka 808-0196, Japan
| | - Kiyohisa Natsume
- Department of Brain Science and Engineering, Graduate School of Life Science and Systems Engineering, Kyusyu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyusyu, Fukuoka 808-0196, Japan; Research Center for Bio-microsensing Technology, Kyusyu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyusyu, Fukuoka 808-0196, Japan; Biomedical Informatics R&D Center, Kyusyu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyusyu, Fukuoka 808-0196, Japan.
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Matzen J, Buchheim K, Holtkamp M. Circadian dentate gyrus excitability in a rat model of temporal lobe epilepsy. Exp Neurol 2011; 234:105-11. [PMID: 22226597 DOI: 10.1016/j.expneurol.2011.12.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Revised: 11/16/2011] [Accepted: 12/13/2011] [Indexed: 10/14/2022]
Abstract
In human mesial temporal lobe epilepsy (mTLE), seizure occurrence peaks in the late afternoon and early evening. This temporal binding of seizures has been replicated in animal models of mTLE following electrically-induced status epilepticus (SE). We hypothesized that in chronic epilepsy, alterations of circadian excitatory and inhibitory functions of the dentate gyrus (DG), which is believed to regulate the generation of limbic seizures, pathophysiologically contribute to the temporal binding of ictogenesis. We performed electrophysiological single and paired pulse measurements hourly over 24h in the DG of epileptic rats (n=8) 8 weeks after electrically induced SE. Results were compared to individual data obtained before induction of SE and to those of control animals (n=3). Pre and post SE data were analyzed in two distinct phases of the day, i.e. a high-seizure phase between 2p.m. and 10p.m. and a low-seizure phase between 10p.m. and 2p.m. In chronic epileptic animals, latency of evoked potentials was significantly reduced in the high-seizure phase (p=0.027) but not in the low-seizure phase. Compared to baseline values, paired pulse inhibition was significantly increased during the low-seizure phase (interpulse interval (IPI) 25ms, p=0.003; IPI 30ms; p<0.001) but not in the high-seizure phase. Similarly, when compared to controls, inhibition at IPI 20ms was diminished only in the high-seizure phase (p=0.027). Thus, in chronic epileptic animals, DG excitability is increased in the afternoon and early evening possibly contributing to the time of day-dependency of spontaneous seizures in this model system of mTLE. Alterations of circadian DG excitability in epileptic animals may be influenced by changes in hypothalamus-regulated superordinate functions such as excretion of endocrine hormones but further studies are needed.
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Affiliation(s)
- Julia Matzen
- Department of Neurology, Otto-von-Guericke-Universität, Magdeburg, Germany
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Abstract
The goal of this study is to investigate the possible circadian regulation of hippocampal excitability and long-term potentiation (LTP) measured by stimulating the Schaffer collaterals (SC) and recording the field excitatory postsynaptic potential (fEPSP) from the CA1 dendritic layer or the population spike (PS) from the soma in brain slices of C3H and C57 mice. These 2 strains of mice were of interest because the C3H mice secrete melatonin rhythmically while the C57 mice do not. The authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from night slices compared to day slices of both C3H and C57 mice. They also found significant diurnal variation in the decay of LTP measured with fEPSPs, with the decay slower during the night in both strains of mice. There was evidence for a diurnal rhythm in the input/output function of pyramidal neurons measured at the soma in C57 but not C3H mice. Furthermore, LTP in the PS, measured in slices prepared during the day but recorded during the night, had a profile remarkably similar to the night group. Finally, PS recordings were carried out in slices from C3H mice maintained in constant darkness prior to experimentation. Again, the authors found that the magnitude of the enhancement of the PS was significantly greater in LTP recorded from subjective night slices compared to subjective day slices. These results provide the 1st evidence that an endogenous circadian oscillator modulates synaptic plasticity in the hippocampus.
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Affiliation(s)
| | | | - Christopher S. Colwell
- To whom all correspondence should be addressed: Christopher S. Colwell, Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA 90024-1759; e-mail:
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Sweeney JE, Lamour Y, Bassant MH. Arousal-dependent properties of medial septal neurons in the unanesthetized rat. Neuroscience 1992; 48:353-62. [PMID: 1603324 DOI: 10.1016/0306-4522(92)90495-n] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have performed a qualitative and quantitative analysis of the electrophysiological properties of medial septal neurons in the unanesthetized rat. The rat's head was held in a stereotaxic apparatus by a painless head-restrained system that was implanted seven days prior to the recording sessions. Extracellular recordings were made in a mixed population of antidromically identified septohippocampal neurons and unidentified medial septal neurons in different states of arousal and in response to peripheral and reticular stimulations. The spontaneous activity as well as the percentage of rhythmically bursting septal neurons varied significantly according to the state of arousal. Higher values were noted in paradoxical sleep (28 imp/s and 94% of bursting neurons) as compared with wakefulness with hippocampal theta rhythm (17.4 imp/s and 64.2% of bursting neurons) and slow wave sleep (12.3 imp/s and 8% of bursting neurons). The frequency of the bursts was significantly higher during paradoxical sleep. In individual medial septal neurons, arousing stimuli and paradoxical sleep could induce rhythmic bursting activity in previously non-bursting neurons provided that they were fast-firing neurons. No differences were noted in the functional characteristics of neurons in the medial septal nucleus as compared with the diagonal band of Broca. When the unanesthetized rats were compared with a group of urethane-anesthetized rats, the spontaneous activity was higher and more irregular in the absence of anesthesia. The percentage of the bursting neurons was significantly lower in the unanesthetized rats (32.3% vs 43.3%). However, the frequency of the bursts was higher (5.9 +/- 0.1 Hz vs 3.5 +/- 0.1 Hz). Since the patterns of activity of medial septal neurons fluctuate in different physiologically relevant states, previous classifications of these neurons made by ourselves and other authors, in urethane-anesthetized rats, may not be appropriate.
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Bijak M. Daily changes in the mouse cingulate cortex responsivity to neurotransmitters and depolarizing medium: an extracellular in vitro study. GENERAL PHARMACOLOGY 1988; 19:107-11. [PMID: 2894331 DOI: 10.1016/0306-3623(88)90014-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
1. The reaction of the mouse cingulate cortex neurons to the applied substances, measured as changes in the spontaneous activity, was investigated for daily variations in the in vitro slice preparation. 2. Glutamate- and GABA-evoked excitation and inhibition, respectively, were followed by long-lasting after-effects which showed greater potency in slices prepared in the evening. 3. Acetylcholine evoked excitation, inhibition and multiphasic effects. The incidence of an excitatory reaction prevailed in slices prepared in the evening. 4. The majority of cells studied in the evening were inhibited after application of a depolarizing medium, while in the morning the reaction was equally divided between excitation and inhibition. 5. The obtained results suggest that a day-night modulation is imposed upon the reactivity of the cingulate cortex neurons, and that daily changes in the reactivity are observed in vitro.
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Affiliation(s)
- M Bijak
- Polish Academy of Sciences, Institute of Pharmacology, Kraków
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