Exposure to music in the perinatal period enhances learning performance and alters BDNF/TrkB signaling in mice as adults.

Music has been suggested to have a beneficial effect on various types of performance in humans. However, the physiological and molecular mechanism of this effect remains unclear. We examined the effect of music exposure during the perinatal period on learning behavior in adult mice, and measured the levels of brain-derived neurotrophic factor (BDNF) and its receptor, tyrosine kinase receptor B (TrkB), which play critical roles in synaptic plasticity. In addition, we measured the levels of 3-phosphoinositide-dependent protein kinase-1 (PDK1) and mitogen-activated protein kinase (MAPK), downstream targets of two main pathways in BDNF/TrkB signaling. Music-exposed mice completed a maze learning task with fewer errors than the white noise-exposed mice and had lower levels of BDNF and higher levels of TrkB and PDK1 in the cortex. MAPK levels were unchanged. Furthermore, TrkB and PDK1 protein levels in the cortex showed a significant negative correlation with the number of errors on the maze. These results suggest that perinatal exposure of mice to music has an influence on BDNF/TrkB signaling and its intracellular signaling pathway targets, including PDK1, and thus may induce improved learning and memory functions.


Effect of repetitive transcranial magnetic stimulation applied over the premotor cortex on somatosensory-evoked potentials and regional cerebral blood flow.

Somatosensory-evoked potentials (SEPs) are attenuated by movement. This phenomenon of 'gating' reflects sensorimotor integration for motor control. The frontal N30 component after median nerve stimulation was shown to be reduced in amplitude prior to hand movement. To investigate the mechanism of this sensory gating, we recorded median SEPs immediately before and after application of monophasic very low-frequency (0.2 Hz) repetitive transcranial magnetic stimulation (rTMS) of 250 stimuli over motor cortex (MC), premotor cortex (PMC), or supplementary motor area (SMA) in 9 healthy volunteers. The stimulus intensity for MC or PMC was set 85% of the resting motor threshold for the hand muscle, and that for SMA was at the active motor threshold for the leg muscle. SEPs showed significant increases in amplitudes of the frontal N30 component after PMC stimulation, but not after SMA or MC stimulation. Low-frequency (1 Hz) biphasic stimulation over PMC showed no significant N30 changes in 6 out of 9 subjects tested, indicating the effect being specific for 0.2 Hz monophasic stimulation. To examine the functional anatomy of the N30 change, single photon emission computed tomography was performed immediately before and after monophasic 0.2 Hz rTMS over PMC in all the 9 subjects. Regional cerebral blood flow showed significant increases mainly in PMC and prefrontal cortex, indicating the involvement of these cortical areas in sensory input gating for motor control.


Monoamine Oxidase A Activity and Norepinephrine Level in Hippocampus Determine Hyperwheel Running in SPORTS Rats.

An understanding of neurological mechanisms for wheel running by rodents, especially with high exercise activity, would be applicable to a strategy for promotion of exercise motivation in humans. One of several brain regions that are candidates for the regulation of physical exercise is the hippocampus. Here we examined the running activity of Spontaneously-Running-Tokushima-Shikoku (SPORTS) rat, a new animal model for high levels of wheel-running activity, and its relation with the hippocampal norepinephrine (NE) system including the levels of NE, adrenergic receptors, and degradation enzymes for monoamines. In the hippocampus of SPORTS rats, the level of NE in extracellular fluid was augmented, whereas the level in the homogenate of the whole tissue was decreased even for sedentary conditions. Elevated extracellular NE caused downregulation of alpha(2)-adrenergic receptors in the hippocampus of SPORTS rats. Local administration of alpha(2)-adrenergic receptor antagonist yohimbine, but not of alpha(2)-agonist clonidine, into the hippocampus suppressed high running activity in SPORTS rats. The protein expression and the activity levels of monoamine oxidase A (MAOA), a critical enzyme for the degradation of NE, were decreased in the hippocampus of SPORTS rats to increase extracellular NE level. Thus, inhibition of oxidase activity in normal Wistar rats markedly increased wheel-running activity. These results indicate that decreased MAOA activity, elevation of extracellular NE, and alpha(2)-adrenergic receptors in the hippocampus determine the neural basis of the psychological regulation of exercise behavior in SPORTS rats.


Arterial Pressure and Heart Rate Increase during REM Sleep in Adenosine A2A-Receptor Knockout Mice, but not in Wild-Type Mice

Rapid eye movement (REM)-sleep related changes in arterial pressure (AP) and heart rate (HR) were observed in homozygous and heterozygous adenosine A(2A) receptor (A2AR) knockout (KO) mice, and the corresponding wild-type mice. During REM sleep, the mean AP (MAP) and HR were clearly increased in the homozygous A2AR KO mice, while, in the wild-type mice, they were decreased or maintained at the same level. Neither homozygous nor heterozygous A2AR KO mice showed significant difference in diurnal pattern and the hourly values of MAP and HR compared to the wild-type mice. From these findings, it is likely that the adenosine A2AR is involved in autonomic regulation during REM sleep.


Effects of cholecystokinin (CCK)-8 on hypothalamic oxytocin-secreting neurons in rats lacking CCK-A receptor

Peripheral administration of cholecystokinin (CCK)-8 selectively activates oxytocin (OXT)-secreting neurons in the supraoptic (SON) and the paraventricular nuclei (PVN) with the elevation of plasma OXT level in rats. We examined the effects of intravenous (iv) administration of CCK-8 on the neuronal activity of hypothalamic OXT-secreting neurons and plasma OXT level in Otsuka Long-Evans Tokushima Fatty (OLETF) rats that have a congenital defect in the expression of the CCK-A receptor gene. In situ hybridization histochemistry (ISH) for c-fos mRNA revealed that the expression of the c-fos gene was not induced in the SON, the PVN, the nucleus of the tractus solitarius (NTS) and the area postrema (AP) 30 min after iv administration of CCK-8 (20 and 40 microg/kg) in OLETF rats. In Long-Evans Tokushima Otsuka (LETO) rats (controls), c-fos mRNA was detected abundantly in those nuclei 30 min after iv administration of CCK-8 (20 microg/kg). Immunohistochemistry for c-fos protein (Fos) showed that the distributions of Fos-like immunoreactivity (LI) were identical to the results obtained from ISH. Dual immunostaining for OXT and Fos revealed that Fos-LI was mainly observed in OXT-secreting neurons in the SON and the PVN of LETO rats 90 min after iv administration of CCK-8 (20 microg/kg). Radioimmunoassay for OXT and arginine vasopressin (AVP) showed that iv administration of CCK-8 did not cause significant change in the plasma OXT and AVP levels in OLETF rats, while iv administration of CCK-8 caused a significant elevation of plasma OXT level without changing the plasma AVP level in LETO rats. These results suggest that peripheral administration of CCK-8 may selectively activate the hypothalamic OXT-secreting neurons and brainstem neurons through CCK-A receptor in rats.

Autonomic Neuroscience : Basic & Clinical


Enhanced hippocampal acetylcholine release in nociceptin-receptor knockout mice

Nociceptin (NOC), an endogenous ligand of the opioid receptor-like 1 receptor, is thought to be involved in learning and memory processes. Since acetylcholine (ACh) is involved in hippocampal function, and the hippocampus plays a critical role on the learning and memory function, hippocampal ACh release in NOC-receptor knockout mice was examined using an in vivo microdialysis method. The release of hippocampal ACh was largely increased in the knockout mice. Furthermore, in the knockout mice, an enhanced hippocampal theta rhythm, which is known to be linked to hippocampal memory function, was also observed. Immunohistochemically, in septum, co-existence of NOC receptor with cholinergic, but not with GABAergic neurons, was verified. The findings demonstrate that the NOC receptor is involved in hippocampal cholinergic function.


Effect of mood state on anticipatory postural adjustments.

Static postural control has been demonstrated to link with psychological state. However, the effect of psychological state on dynamic postural control remains unclear. In this study, we examined the effect of mood state on anticipatory postural adjustment (APA), one of the most important functions for dynamic postural control. Fourteen healthy male subjects performed unilateral arm elevation tasks after completing a Profile of Mood States (POMS) questionnaire. Mood state measured by POMS and the latency or amplitude of the APA in the ventral muscles (rectus femoris, tibialis anterior) of the lower limb showed significant negative correlations. The correlation between the mood state and APA amplitude in the soleus was found to be significantly positive. There were significant negative correlations between the mood state and reaction-time. These findings suggest that it is possible that dynamic postural control is affected by mood state.


Lack of nociceptin receptor alters body temperature during resting period in mice

The role of nociceptin (NOC) receptor on body core temperature (Tcore) control was examined using NOC receptor knockout mice. In homozygote NOC receptor-knockout, wild-type, and control C57BL/6J and 129/SV mice, Tcore was continuously recorded under 12:12 h light:dark (LD) and conditions of constant darkness (DD). The Tcore values during the resting period were higher in the NOC receptor-knockout mice than in both wild-type and control mice under both LD and DD conditions. Spontaneous activity during the resting period and plasma cortisol levels were not different between the NOC receptor-knockout and control mice. The findings herein indicate that the NOC receptor is involved in the control of Tcore during the resting period and is independent of light, physical activity and/or cortisol regulation.


Six-hour selective REM sleep deprivation increases the expression of the galanin gene in the hypothalamus of rats.

The effect of short-term selective REM sleep deprivation (RSD) on the gene expression of galanin in the rat hypothalamus was examined using in situ hybridization histochemistry. Monitoring an electroencephalogram (EEG) and electromyogram (EMG) on an on-line computer screen, as the RSD rats entered REM sleep, they were gently stroked on their backs using a brush to wake them during the RSD period. Galanin mRNA levels in the preoptic area (POA) were significantly increased by RSD for a period of 6 h. RSD had no significant effect on the mRNA levels of corticotrophin-releasing factor (CRF), arginine vasopressin (AVP), oxytocin (OXT) or orexins. These results suggest that 6-h selective RSD may not be sufficient to induce the activation of the hypothalamo-pituitary adrenal axis, and that the expression of the galanin gene in the hypothalamus reacts more readily against the loss of REM sleep in comparison to other hypothalamic neuropeptides such as arginine vasopressin, oxytocin and orexins.

Brain Research. Molecular Brain Research


Prenatal exposure to alchol alters the light response in postnatal circadian rhythm

We studied the effect of prenatal exposure to alcohol on later circadian rhythm in the rat. In the normal light-dark cycle, an 8-h phase advance brought forward the deep body temperature rhythm in control rats, although it had a smaller effect in prenatally ethanol-exposed rats. In long constant darkness, the phase response of the deep body temperature rhythm to a light pulse at the early subjective night was less marked in ethanol-exposed rats in comparison to controls. These results indicate that prenatal exposure to alcohol has a long-lasting effect on the light responsiveness of the deep body temperature circadian rhythm.


Sex difference in circadian period of body temperature in Clock mutant mice with Jcl/ICR background

The period of circadian rhythm remains remarkably stable in both sexes under conditions of constant darkness. Several studies have indicated that gonadal hormones such as estradiol shorten the period of circadian rhythms. We observed that the free-running period of core body temperature is longer in male homozygous Clock mutant mice than in females, although this difference is not found in wild mice. Furthermore, a gonadectomy had no effect on the period of core body temperature in either sex. This suggests the existence of a sex-related difference of the mammalian circadian system, and that it is independent of peripheral gonadal regulations.


Tactile visual cross-modal shape matching: a functional MRI study

The process and location of integration of information from different sensory modalities remains controversial. We used functional MRI to investigate the neural representation of cross-modal matching between tactile and visual shape information in eleven normal volunteers. During the scan, patterns of 2D shapes were presented both tactually and visually, simultaneously. Four different matching tasks were performed: tactile-tactile with eyes closed (TT), tactile-tactile with visual input (TTv), visual-visual with tactile input (VVt), and tactile-visual (TV). The TT task activated the contralateral primary sensorimotor area, and the postcentral gyrus, superior parietal lobules, anterior portion of the intraparietal sulcus, secondary somatosensory cortex, thalamus, dorsal premotor area, cerebellum, and supplementary motor area bilaterally, without occipital involvement. Visual matching activated the primary visual cortex and the lingual and fusiform gyri bilaterally. A cross-modal area was identified by subtracting TTv images from TV images, subtracting VVt images from TV images, and then determining common active areas. There was one discrete area that was active bilaterally; the posterior intraparietal sulcus close to the parieto-occipital sulcus. These data suggest that shape information from different sensory modalities may be integrated in the posterior intraparietal sulcus during tactile-visual matching tasks.

Brain Research. Cognitive Brain Research


Single eight-hour shift of light-dark cycle increases brain-derived neurotrophic factor protein levels in the rat hippocampus

We previously reported that an eight hour phase advance in the light-dark (LD) cycle increases sleep in rats. Brain-derived neurotrophic factor (BDNF) is suggested to be one of the sleep and circadian regulating factors. We have therefore observed the responses of BDNF protein in the hippocampus, cerebellum and brainstem under conditions of LD change. BDNF protein was quantitatively measured using an ELISA kit. Under an 8-h LD phase advance, the levels of hippocampal BDNF were significantly increased on the day of the phase change, while the levels in the cerebellum and brainstem remained constant. Plasma corticosterone levels were not largely affected. Thus, a single LD shift acutely affects hippocampal BDNF metabolism with no large stress response.


Increase of hippocampal acetylcholine release at the onset of dark phase is suppressed in a mutant mice model of evening-type individuals.

We have previously reported that clock mutant mice on Jcl:ICR background show about 2-h delayed circadian profiles in body temperature, spontaneous activity and sleep-wake rhythm, and that they appear to be useful as a model of evening-type of individual. Hippocampal acetylcholine (ACh) release which is positively correlated with attention, learning and memory shows a circadian variation. In this study, changes in hippocampal ACh release in transitional phase from light (rest) to dark (active) period in clock mutant mice were monitored using an in vivo microdialysis method. Compared with wild mice, the increase in hippocampal ACh in the first 2 h of the active period in the mutant mice was suppressed in parallel with peak frequency in electroencephalogram theta rhythm. The molecular basis of the circadian system appears to have a strong effect on hippocampal cholinergic function, and is probably associating with individual temporal differences in voluntary behavior, cognition, learning and/or memory performance.


Changes in the expression of steroid metabolism-related genes in rat adrenal glands during selective REM sleep deprivation

Selective REM sleep deprivation was carried out under the conditions designed to minimize the adverse influence of environmental conditions and restricted movement, and the influence of REM sleep deprivation on adrenocortical steroid metabolism was investigated by measuring the steady-state levels of mRNAs encoding steroid metabolism-related genes, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme cytochrome P450 (P450scc) and steroid 5alpha-reductase (5alpha-R), in rat adrenal glands. Selective REM sleep deprivation caused a significant decrease in StAR mRNA and an increase in 5alpha-R mRNA levels without any notable change in P450scc mRNA levels in the adrenal gland. In contrast, non-selective sleep disturbance, resulting in the partial reductions of non-REM and REM sleep, tended to increase both StAR and P450scc mRNA levels without any statistical significance. These results indicate that REM sleep deprivation by itself may affect the expression of steroid metabolism-related genes in the adrenal gland, suggesting a possible relation between REM sleep and adrenocortical steroid metabolism.


Premovement gating of somatosensory evoked potentials after tibial nerve stimulation

Somatosensory evoked potentials (SEPs) are attenuated or gated during movement. The mechanism for this includes both centrifugal gating of afferent input and competition with other afferents caused by the movement (peripheral gating). Using a paradigm in which the signal for triggering movement is the electric stimulus for SEPs, we studied the gating of SEPs after tibial nerve stimulation prior to foot movement, and compared it with that during counting task. Significant gating was found for P40 component, which distributed centrally and ipsilaterally to the side of the stimulation, whereas the contralateral N40 component showed no changes. Dissociated gating of P40 and N40 indicates multiple generators of these components, in contrast to the previous view of a single generator dipole projecting tangentially. Together with the previous findings in median SEPs, these gating phenomena should represent a general mechanism for sensori-motor integration in preparation for limb movement.


Levodopa improved rapid eye movement sleep behavior disorder with diffuse Lewy body disease


Short-term sleep disturbance enhances BDNF gene expression in rat hippocampus by acting as internal stressor

Rats were subjected to nonselective sleep disturbance for short periods under conditions designed to minimize the adverse influence of external stresses, such as environmental conditions and restricted movement, and both brain-derived neurotrophic factor (BDNF) protein and its mRNA levels in the brain were then determined to investigate the influence of sleep disturbance itself on BDNF gene expression. Total sleep duration was partially but significantly reduced by disturbing the sleep/wake cycle for 1 and 2 h, gradually increased according to the time of disturbance, then returned to control levels at 6 h after the beginning of sleep disturbance. Under these conditions, the slight but significant elevation of corticotrophin-releasing factor (CRF) mRNA levels in the paraventricular nucleus (PVN) was observed at an early stage of the sleep disturbance period. Sleep disturbance induced the elevation of both BDNF protein and its mRNA levels in the hippocampus but not in the cerebellum or the brainstem, and the elevated BDNF mRNA expression in the hippocampus returned toward basal levels during the sleep recovery period when the rebound of sleep duration was observed. These findings suggest the possibility that short-term disturbance of the sleep/wake cycle and, hence, the partial reduction of non-REM sleep duration, might exert a potential influence on neuronal and/or glial cells as an internal stressor, resulting in the elevation of BDNF gene expression in rat hippocampus.


REM sleep deprivation suppresses acquisition of classical eyeblink conditioning

The aim of this study was to investigate the issue of whether REM sleep is involved in implicit learning through the cerebellum-related neural circuit via the use of classical eyeblink conditioning (CEC). Subjects were divided into three groups: control (sleep without interruption), REM sleep deprivation (RD), and slow wave sleep (stage 3+4) deprivation (SD). The CEC was performed after 8 hours of ordinary nocturnal sleep or sleep disrupted at a selected sleep stage. A university-based sleep laboratory. Twenty-seven healthy volunteers (all men, aged 23.2+/-0.6 years). The CEC was measured after selective sleep deprivation or ordinary nocturnal sleep. The eyeblink reflex was conditioned using a classical delay conditioning paradigm. The conditioned response (CR) was determined by electromyography measurements of the orbicularis oculi muscles. The rate of appearance of the CR was compared among the three groups. Compared with the control subjects, RD subjects were significantly deficient in their capacity to acquire conditioned eyeblinks, while no difference was found among the SD subjects. This study suggests that RD suppresses the cerebellar function in CEC and that REM sleep is closely linked with the learning function in the cerebellum.


Age-related changes in control of blood pressure and heart rate during sleep in the rat

The aim of this study was to determine age-related changes in the control of mean arterial pressure (MAP) and heart rate (HR) during sleep, and its relationship to the baroreflex in aging. MAP, HR, body temperature (TP), spontaneous activity (ACT), and sleeping/waking duration were monitored for 24 hours in groups of young (10-12 wk old) and old (23-24 mo old) rats. The sleep laboratory at the University of Tokushima. Subjects were 8 young (10-12 wk old) and 7 old (23-24 mo old) Wistar rats. Reflex control of HR was evaluated by examining various pressure responses to an intravenous bolus injection of phenylephrine and sodium nitroprusside. MAP and TP were recorded by a radiotelemetry system. HR was detected from the AP signal. ACT was counted by a photo-sensor system. In the case of old rats, the sensitivity of baroreflex control of HR was significantly depressed, and the spontaneous increase of MAP and HR during REM sleep and the MAP drop at the end of REM sleep were significantly enhanced. The old rats showed no large deterioration of the circadian profiles of MAP, HR, TP, and the amount of sleep. The baroreflex dysfunction is considered to appear in an early stage of the aging process, and to affect the control of MAP and HR during sleep.


Mesolimbic dopaminergic system is involved in diurnal blood pressure regulation

Parkinson's disease (PD) patients with autonomic failure show no nocturnal decrease in blood pressure (BP). At present, it is not clear if this symptom is attributable to the disturbance of the dopaminergic (DA) system that is responsible for PD. In the present study, we determined that the mesolimbic DA system is involved in diurnal profiles of the mean BP (MBP) by destroying the A10 DA system in rats with 6-hydroxydopamine. In control rats, a clear dip in the MBP and heart rate (HR) occurs during the light, that is, resting period, analogous to the nocturnal dip in normal humans. This normal daytime decrease in MBP and HR was disturbed by inducing a lesion of the ventral tegmental area (VTA) DA neurons, although the rhythms of wake-sleep duration and behavioral activity remained relatively intact. On the basis of this evidence, the absence of a nocturnal dip in BP in PD patients is attributed to impairment of the mesolimbic DA system.


Influence of sleep disturbance on steroid 5a-reductase mRNA levels in rat brain

Sleep deprivation has been shown to affect the production of steroid hormones in peripheral steroidogenic organs, but little is known about the influence of sleep disturbance on the metabolism of steroid hormones in the brain. To elucidate a possible association of the sleep-wake cycle with brain neurosteroid metabolism, the influence of short-term sleep disturbance on the expression of mRNA encoding steroid 5alpha-reductase, the enzyme converting progesterone and other steroid hormones to their neuroactive 5alpha-reduced metabolites, was investigated. Rats were first subjected to non-selective disturbance of the sleep-wake cycle, and the expression of steroid 5alpha-reductase mRNA in rat hippocampus and brainstem was determined using a semi-quantitative one-step RT-PCR technique. Non-selective disturbance of the sleep-wake cycle resulted in the elevation of 5alpha-reductase mRNA levels in the brainstem, but not in the hippocampus, and the elevated mRNA expression returned to the basal levels after a short period of the sleep recovery. Further studies showed that selective REM sleep deprivation significantly elevated 5alpha-reductase mRNA levels in both hippocampus and brainstem, thus proposing the possibility that REM sleep reduction may largely contribute to the elevation of steroid 5alpha-reductase mRNA levels observed during short-term disturbance of the sleep-wake cycle. Since the enhancement of steroid 5alpha-reductase gene expression may result in the elevation of neuroactive 5alpha-reduced steroid production in the brainstem, the findings presented here provide further evidence for suggesting that neuroactive steroids may play a physiologically important role in the neuronal network for REM sleep initiation and maintenance.


Semi-quantitative RT-PCR analysis of environmental influence on P450scc and PNMT mRNA expression in rat adrenal glands

Environmental influence on brain function, particularly spatial learning and memory, has been extensively investigated, but little is known about the influence of environmental conditions on the functions of peripheral organs. In the present study, the effects of different housing conditions on the steady-state levels of mRNAs encoding cholesterol side-chain cleavage enzyme (cytochrome P450scc) and phenylethanolamine N-methyltransferase (PNMT) in adrenal glands was examined to investigate the environmental influence on both adrenocortical and adrenomedullary functions. Behavioral changes of the animals housed in different conditions were first examined to assess the relevance of environmental manipulation used. In consistent with previous findings, housing of the animals in enriched conditions resulted in the significant reduction of spontaneous motor activity (locomotor activity and rearing) in comparison with housing in isolated conditions, thus indicating the relevance of housing conditions used in this work for investigating the environmental influence on adrenal function. Then, the effects of these housing conditions on P450scc and PNMT mRNA levels in adrenal glands were examined using semi-quantitative RT-PCR method. In comparison with the isolated group, the enriched group showed significantly higher levels of P450scc mRNA. In contrast, PNMT mRNA levels in the enriched group were significantly lower than those in the isolated group. These results propose the possibility that the environmental conditions may cause differential alterations in adrenocortical and adrenomedullary functions, although their possible association with behavioral changes still remains to be elucidated.


Event related Potentials in a patient with word meaning aphasia with special referencce to topography --- とくにそのトポグラフィーについて

語義失語症例の事象関連電位 --- とくにそのトポグラフィーについて

外傷による語義失語と正常対照群および典型失語群の漢字，仮名課題における事象関連電位(ERP)とそのトポグラフィーを比較検討した．語義失語例では漢字·かなともにコントロール群，典型失語群に比べP200が高振幅であったが，P300は不明瞭であった．P200振幅は受症36ヶ月では漢字課題において，課題正答率の増大とともに減衰した．またトポグラフィーでこのP200は左右頭頂後頭部に特異的な分布を示した．


Human morning/evening preferences has recently been reported to be associated with polymorphism of the 3' flanking region of the Clock gene, which was the first identified mammalian circadian clock gene. We recorded body temperature, spontaneous activity, electroencephalogram and electromyogram for 48 h in mice with Jcl:ICR genetic background and homozygous for the Clock mutation (Cl/Cl on Jcl:ICR). In both wild-type and Cl/Cl on Jcl:ICR, body temperature, activity, wake and sleep were completely entrained to LD cycle. However, phases of the rhythm for body temperature, activity and wake duration in the Cl/Cl on Jcl:ICR were about 2 h delayed in comparison with the wild-type. This study has provided further evidence on the close relationship between human morning/evening preference and the molecular basis of circadian clock system, and has suggested that Cl/Cl on Jcl:ICR is useful for an animal model for human morning/evening preference.


Differential effect of short-term REM sleep deprivation on NGF and BDNF protein levels in the rat brain

It is well known that REM sleep is associated with memory consolidation, especially, procedural skill learning. Neurotrophic factors are known to be involved in synaptic plasticity. We therefore investigated the effects of selective REM sleep deprivation (RSD) on NGF and BDNF proteins in the hippocampus, cerebellum and brainstem in the rat. NGF and BDNF were detected by an ELISA. Our findings show that 6 h RSD affected the NGF and BDNF protein levels in different manner. In the cerebellum and brainstem, BDNF was significantly decreased, while NGF was not changed. Conversely, in the hippocampus, NGF was significantly decreased while BDNF was not changed. This study indicates that REM sleep may be associated with the secretion of neurotrophic factors and thus contribute to the memory functions.


Sympathetic activity in alexithymics with mother's low care


Injection of 6-hydroxydopamine into the ventral tegmental area suppresses the increase in arterial pressure during REM sleep in the rat


Influence of cedar essence on spontaneous activity and sleep of rats and human daytime nap


Influence of cedar essence on spontaneous activity and human daytime nap.

We investigated whether exposure to the odor of extracted cedar essence (CE) has (i) an influence on spontaneous activity and sleep-wake states of rats and (ii) a sleep-promoting effect on human daytime nap after taking an ordinary night's sleep. In rats exposed to CE, spontaneous activities and amount of wake were significantly decreased, while the amount of non-rapid eye movement (NREM) sleep was significantly increased. In human daytime nap, NREM sleep stage 2 latency was significantly shortened after exposure to CE.


The Effects of Acetazolamide on Arterial Pressure Variability During REM Sleep in the Rat


Diurnal Change of Arachidonate 12-Lipoxygenase in Rat Pineal Gland

Biochemical and Biophysical Research Communications


Sleep characteristics of Japanese working men who score alexithymic on the Toronto Alexithymia Scale


Effect of vitamin B12 on the sleep-wake rhythm following an 8-hour advance of the light-dark cycle in the rat


Mothers' low care in the development of alexithymia: a preliminary study in Japanese college students

We examined the influences of perceived parental bonding on scores on alexithymia in a sample of 232 college students. Ratings on mothers' care, a scale of the Parental Bonding Inventory were significantly and negatively correlated with scores on the Toronto Alexithymia Scale, and also with ratings on Difficulty Describing Feelings but not Difficulty Identifying Feelings and Externally Oriented Thinking. These results were replicated in another sample of 156 college students. Although our findings were based on simple correlations, they suggest that perceived mothers' low care is related to adults' scores on alexithymia, in particular, the construct, Difficulty Describing Feelings.


Acceleration of EEG theta wave precedes the phasic surge of arterial pressure during REM sleep in the rat

We investigated temporal relationships among EEG theta frequency, eye movement (EM) burst and phasic surge of arterial pressure (AP) during rapid eye movement (REM) sleep in six rats. Changes in EEG theta frequency, EM number, mean AP (MAP) and heart rate (HR) during 1 s bins were obtained with reference to the onset of the EM bursts. The acceleration of EEG theta frequency preceded both the EM burst and the phasic increases of AP. The increase of MAP was closely correlated with the theta frequency but not the EM number during the period of EM burst. The possible involvement of the limbic system for the generation of phasic surge in AP during REM sleep is discussed.


Effect of ambient temperature on power spectral density of arterial pressure during sleep in the rat


Effect of ambient temperature on arterial pressure variability during sleep in the rat


Heart rate variability during sleep in Down's syndrome


Light-dark difference in arterial pressure variability during REM sleep in the rat.

逆説睡眠時には血圧が相動性に変動する．この血圧ゆらぎを経時的に解析した結果，ゆらぎの大きさは記録された時刻によってことなり，概日リズムが存在することが明らかとなった．


Effects of intravenously administered vitamin B12 on sleep in the rat


Postoperative changes of rat EEG variance


Diurnal changes of blood pressure, heart rate and body temperature during sleep in the rat


Relationship between eye movements and oneiric behavior in cats


Effects of an eight-hour advance of the light-dark cycle on sleep-wake rhythm in the rat


Ultradian rhythm of 100 min in the dark phase EEG of the rat


Real-time monitoring of slow-wave sleep by electroencephalogram variance


Diurnal changes in pineal extracellular indoles of freely moving rats.


Pineal microdialysis in freely moving rats.


Concurrent on-line sampling of melatonin in pineal microdialysates from conscious rat and its analysis by high-performance liquid chromatography with electrochemical detection

Dynamic changes of melatonin in microdialysates from the pineal gland of a freely moving rat were repeatedly determined by using on-line high-performance liquid chromatography with electrochemical detection. The detection limit for melatonin, ca. 5 pg, was well below that achieved with other systems. We observed a drastic increase of extracellular pineal melatonin during the transitional phase from the light period to the dark period. This application of microdialysis is a useful tool in the study of the physiological role of the mammalian pineal body.

Journal of Chromatography. B, Biomedical Sciences and Applications


Effect of videogame on sleep, mood in children


Long-term profiles of sleep-related hemodynamic changes in the postoperative chronic cat


老齢ラット線条体モノアミン代謝の日内変動と睡眠·覚醒リズム --- 脳内透析法による検討


Effects of a weak diffuse-brain-stimulation on insomniacs with vibration syndrome


Transitional mechanism from sleep to arousal in cats


Arousal mechanism from sleep in cats (2): a brain electrostimulation study a brain electrostimulation study


Arousal mechanism with special reference to sympathetic activity


Induction of sleep by electrical stimulation in cats


Revaluation of humoral factors in sleep mechanism


Effect of intravenous infusion of nutrients on hypothermia induced by propofol anesthesia in rats

3大栄養素の静脈内投与がpropofol麻酔時の核心温低下に与える影響

The Japanese Journal of Surgical Metabolism and Nutrition


Cerebral local blood flow with a laser-doppler flowmetry in rat sleep

The Tokushima Journal of Experimental Medicine


Diurnal monoamine variation in young and old rats. --- A microdialysis study


Ultrasonic technique for penile tumescence measurement in rat sleep


老齢ラットにおける睡眠の特徴

老齢ラットにおける睡眠の特徴


Studies of electrosleep on normal adults, insomniacs, hypertensive patients


Sleep in patients with vibration disease