| spectral analysis of mouse eeg after the administration of n,n-dimethyltryptamine. | mice were implanted with permanent cortical electrodes. the eeg was recorded during the sleep-wake cycle and after the administration of n,n-dimethyltryptamine (dmt). based upon spectral analysis the eeg was classified into three categories: awake, slow-wave sleep (sws), and rapid eye movement sleep (rem). the dominant frequencies were located below 2 hz in the case of sws and between 6 and 9 hz for rem. when dmt was administered intraperitoneally at 20 or 40 mg/kg, a dose-dependent hypersynchro ... | 1977 | 271513 |
| regularly scheduled voluntary exercise synchronizes the mouse circadian clock. | circadian rhythm entrainment has long been thought to depend exclusively on periodic cues in the external environment. however, evidence now suggests that appropriately timed vigorous activity may also phase shift the circadian clock. previously it was not known whether levels of exercise/activity associated with spontaneous behavior provided sufficient feedback to phase shift or synchronize circadian rhythms. the present study investigated this issue by monitoring the sleep-wake, drinking, and ... | 1991 | 1928438 |
| pharmacological properties of (n-dicyclopropylmethyl) amino-2-oxazoline (s 3341), an alpha-2 adrenoceptor agonist. | pharmacological actions of (n-dicyclopropylmethyl)-amino-2-oxazoline (s 3341), an agonist of alpha-2 adrenoceptors, were examined in acute animal studies. in the normotensive anaesthetized dog s 3341 (0.3 mg/kg, i.v.) produced an initial transient increase followed by a marked, prolonged fall in mean arterial pressure (map) of 20 mmhg. central actions of s 3341 were demonstrated by administration of low doses into the vertebral artery of the anaesthetized dog. a rapid and marked fall in map resu ... | 1985 | 2866274 |
| precision of circadian wake and activity onset timing in the mouse. | in each circadian cycle, a mouse begins its major activity period with discrete wake onset and activity onset events. the precision with which these events are timed in constant darkness was analyzed using the approach outlined by pittendrigh and daan (1976). negative serial correlations of observed circadian period values (mean r1 = -0.471 for wake data, -0.409 for activity data) imply that deviations in period tend to be compensated by opposite deviations in the following cycle. as a result, p ... | 1986 | 3735167 |
| effect of age on the circadian pattern of sleep and wakefulness in the mouse. | in elderly humans, daytime naps are common, nocturnal sleep is poorly consolidated, and the sleep period often begins and ends earlier than in young adults. because previous work has suggested that rodents may provide a useful animal model for these changes, we conducted a detailed investigation of sleep patterns in 11 young adult and 9 old mice. mice were surgically implanted for chronic eeg recording, and sleep state was monitored over multiple circadian cycles. during the active phase, old mi ... | 1986 | 3745812 |
| circadian rhythms of sleep and wakefulness in mice: analysis using long-term automated recording of sleep. | circadian rhythms of wheel-running activity and polygraphically defined wakefulness, rapid-eye-movement (rem) sleep and non-rem (nrem) sleep were continuously observed in ten mice (mus musculus) under both alternating light-dark (ld 12:12) and continuous darkness (dd) conditions. sleep-wake state was determined automatically using a computer-based method that allowed continuous recordings of from 60 to 280 days in duration. the sleep-wake state percentages (of the circadian cycle) thus obtained ... | 1985 | 3838419 |
| temperature modulates ethanol sensitivity in mice: generality across strain and sex. | findings in our laboratory indicate that body temperature alters ethanol potency as measured by sleep-time, wake-up brain ethanol concentration and mortality in male c57bl/6j mice. the current studies tested the generality of these results. experiment one tested age-matched, drug-naive, male c57bl/6s and balb/cs mice. experiment two tested age-matched, drug-naive, male and female c57bl/6j mice. each mouse was injected ip with 3.6 g/kg ethanol (20% w/v). after losing its righting reflex, the mous ... | 1985 | 4015848 |
| a circadian rhythm of hippocampal theta activity in the mouse. | hippocampal theta activity dominates the cortical eeg of the mouse during certain behaviors. we have therefore been able to study the circadian distribution of hippocampal theta activity by means of chronic eeg implantation and computerized eeg state scoring. observations in six mice indicate consistent and significant circadian patterns of theta-dominated eeg, both during wakefulness (theta-dominated wake, or tdw) and during sleep (rem sleep). the probability of rem rises gradually to a maximum ... | 1985 | 4070426 |
| effect of chronic rem sleep deprivation on pituitary, hypothalamus and hippocampus pge2 and pgd2 biosynthesis in the mouse. | given the often reported relationships between sleep-wake regulation and the cerebral prostaglandins (pgs), the effect of chronic rapid eye movement (rem) sleep deprivation on brain pge2 and pgd2 biosynthesis in mouse was evaluated, since they are known to have opposite actions as respectively wake- and sleep-inducing substances. mice were subjected to 5 and 10 days of rem sleep deprivation by the flower pot technique. after sacrifice, pge2 and pgd2 were determined in the pituitary, hypothalamus ... | 1994 | 7846109 |
| dna-binding specificity and trans-activating potential of the leukemia-associated e2a-hepatic leukemia factor fusion protein. | hybrid transcription factors, resulting from gene fusions in the wake of chromosomal translocations, have been implicated in leukemogenesis, but their precise contributions to oncogenic conversion remain unclear. the e2a-hlf fusion gene, formed by a t(17;19)(q22;p13) in childhood pro-b-cell acute lymphoid leukemia, encodes a hybrid protein that contains the trans-activation domain of e2a (e12/e47) linked to the bzip dna-binding and dimerization domain of hepatic leukemia factor (hlf). here we re ... | 1994 | 8164688 |
| non-rapid eye movement sleep is suppressed in transgenic mice with a deficiency in the somatotropic system. | sleep-wake activity was studied in a transgenic mouse model (th-hgh) with a deficiency in the somatotropic axis (growth hormone (gh)-releasing hormone (ghrh)-gh-insulin-like growth factor-i (igf-i)). this dwarf transgenic mouse strain expresses a human gh (hgh) reporter gene linked to 4.8 kb of the rat tyrosine hydroxylase flanking sequence, targeting the production of hgh to sites of tyrosine hydroxylase synthesis in the brain. endogenous gh and igf-i are suppressed in these mice, as well as gh ... | 1996 | 8981482 |
| involvement of igf2 and h19 imprinting in choriocarcinoma development. | complete hydatidiform mole is an abnormal pregnancy characterized by grossly swollen villi in the absence of a fetus (kajii and ohama 1997, wake et al., 1978, jacobs et al., 1980). it is well known that this abnormal pregnancy product is androgenetic in origin. the entire genome of the molar conceptus is paternally derived. the majority of moles result from fertilization of an empty egg by haploid sperm. the paternally derived haploid set then duplicated without cytokinesis and restores diploidy ... | 1998 | 9833609 |
| the mouse lymphoma assay in the wake of ich4--where are we now? | | 1999 | 10374993 |
| circadian coordination of cancer growth and metastatic spread. | to understand whether mammalian circadian time structure measurably affects the host-cancer balance, we studied tumor-take frequency after s.c. tumor cell inoculation and the number of pulmonary tumor nodules after i.v. tumor cell injections at each of 6 equispaced times of day. we employed 2 genetically distinct mouse strains and 2 different tumor model systems, a methylcholanthrene a-induced fibrosarcoma of c(3)hej mice and 2 b(16) melanoma cell lines of vastly different metastatic efficiency ... | 1999 | 10495429 |
| the transcription factor dbp affects circadian sleep consolidation and rhythmic eeg activity. | albumin d-binding protein (dbp) is a par leucine zipper transcription factor that is expressed according to a robust circadian rhythm in the suprachiasmatic nuclei, harboring the circadian master clock, and in most peripheral tissues. mice lacking dbp display a shorter circadian period in locomotor activity and are less active. thus, although dbp is not essential for circadian rhythm generation, it does modulate important clock outputs. we studied the role of dbp in the circadian and homeostatic ... | 2000 | 10632591 |
| effects of sleep deprivation on sleep and sleep eeg in three mouse strains: empirical data and simulations. | gene targeted mice can be used as models to investigate the mechanisms underlying sleep regulation. three commonly used background strains for gene targeting (129/ola, 129/svj and c57bl/6j) were subjected to 4-h and 6-h sleep deprivation (sd), and their sleep and sleep eeg were continuously recorded. the two-process model of sleep regulation has predicted the time course of slow-wave activity (swa) in nonrem sleep after several sleep-wake manipulations in humans and the rat [3] [9]. we tested th ... | 2000 | 10700548 |
| cryptochromes: sensory reception, transduction, and clock functions subserving circadian systems. | cryptochromes (crys) are blue-light-absorbing proteins involved in a variety of biological phenomena. in animals, crys exhibit a certain versatility with regard to these organisms' circadian rhythms, as has been revealed by the effects of mutations and molecular manipulations. the rhythm system of drosophila uses one gene's worth of cry protein to transmit light into a circadian clock within the brain, which controls the fly's sleep-wake cycles. in fact, the relevant pacemaking neurons are thems ... | 2000 | 10981614 |
| the circadian clock mutation alters sleep homeostasis in the mouse. | the onset and duration of sleep are thought to be primarily under the control of a homeostatic mechanism affected by previous periods of wake and sleep and a circadian timing mechanism that partitions wake and sleep into different portions of the day and night. the mouse clock mutation induces pronounced changes in overall circadian organization. we sought to determine whether this genetic disruption of circadian timing would affect sleep homeostasis. the clock mutation affected a number of slee ... | 2000 | 11050136 |
| imaging anoxic depolarization during ischemia-like conditions in the mouse hemi-brain slice. | focal ischemia evokes a sudden loss of membrane potential in neurons and glia of the ischemic core termed the anoxic depolarization (ad). in metabolically compromised regions with partial blood flow, peri-infarct depolarizations (pids) further drain energy reserves, promoting acute and delayed neuronal damage. visualizing and quantifying the ad and pids and their acute deleterious effects are difficult in the intact animal. in the present study, we imaged intrinsic optical signals to measure cha ... | 2001 | 11152742 |
| dopaminergic role in stimulant-induced wakefulness. | the role of dopamine in sleep regulation and in mediating the effects of wake-promoting therapeutics is controversial. in this study, polygraphic recordings and caudate microdialysate dopamine measurements in narcoleptic dogs revealed that the wake-promoting antinarcoleptic compounds modafinil and amphetamine increase extracellular dopamine in a hypocretin receptor 2-independent manner. in mice, deletion of the dopamine transporter (dat) gene reduced non-rapid eye movement sleep time and increas ... | 2001 | 11222668 |
| sleep in the blind mole rat spalax ehrenbergi. | the mole rat, spalax ehrenbergi, is an interesting species for sleep because of its pronounced specialization to a fossorial life. these rodents spend most of their life-time underground, and are less exposed to many of the environmental stimuli and challenges that are common to non-fossorial rodents. a prominent adaptation is their blindness, which is due to an atrophy of the eyes. | 2001 | 11247050 |
| the homeostatic regulation of sleep need is under genetic control. | delta power, a measure of eeg activity in the 1-4 hz range, in slow-wave sleep (sws) is in a quantitative and predictive relationship with prior wakefulness. thus, sleep loss evokes a proportional increase in delta power, and excess sleep a decrease. therefore, delta power is thought to reflect sws need and its underlying homeostatically regulated recovery process. the neurophysiological substrate of this process is unknown and forward genetics might help elucidate the nature of what is depleted ... | 2001 | 11306614 |
| mouse model for morningness/eveningness. | 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 completel ... | 2001 | 11388430 |
| dominant localization of prostaglandin d receptors on arachnoid trabecular cells in mouse basal forebrain and their involvement in the regulation of non-rapid eye movement sleep. | infusion of prostaglandin (pg) d(2) into the lateral ventricle of the brain induced an increase in the amount of non-rapid eye movement sleep in wild-type (wt) mice but not in mice deficient in the pgd receptor (dp). immunofluorescence staining of wt mouse brain revealed that dp immunoreactivity was dominantly localized in the leptomeninges (lm) of the basal forebrain but that pgd synthase immunoreactivity was widely distributed in the lm of the entire brain. electron microscopic observation ind ... | 2001 | 11562489 |
| a model of sleep-disordered breathing in the c57bl/6j mouse. | to investigate the pathophysiological sequelae of sleep-disordered breathing (sdb), we have developed a mouse model in which hypoxia was induced during periods of sleep and was removed in response to arousal or wakefulness. an on-line sleep-wake detection system, based on the frequency and amplitude of electroencephalograph and electromyograph recordings, served to trigger intermittent hypoxia during periods of sleep. in adult male c57bl/6j mice (n = 5), the sleep-wake detection system accuratel ... | 2001 | 11717244 |
| behavioral characterization of mice lacking histamine h(3) receptors. | brain histamine h(3) receptors are predominantly presynaptic and serve an important autoregulatory function for the release of histamine and other neurotransmitters. they have been implicated in a variety of brain functions, including arousal, locomotor activity, thermoregulation, food intake, and memory. the recent cloning of the h(3) receptor in our laboratory has made it possible to create a transgenic line of mice devoid of h(3) receptors. this paper provides the first description of the h(3 ... | 2002 | 12130692 |
| cellular localization of cyclooxygenase-1 and cyclooxygenase-2 in the normal mouse, rat, and human retina. | prostaglandins, synthesized by cyclooxygenase (cox), regulate diverse neurophysiological actions such as regulation of autonomic responses, transmission of pain, generation of fever, control of sleep-wake cycle, synaptic signaling, and cross-talk between neurons and glia in the central nervous system. although prostaglandins have been widely studied in the anterior segment tissues of the eye, relatively little is known about prostaglandins in the neural retina. by using immunohistochemistry, we ... | 2002 | 12355421 |
| microinjection of neostigmine into the pontine reticular formation of c57bl/6j mouse enhances rapid eye movement sleep and depresses breathing. | the cholinergic model of rapid eye movement (rem) sleep has contributed significantly to understanding sleep neurobiology and sleep-dependent respiratory depression. the model has been used extensively in cat and rat, but no previous studies have demonstrated cholinergic rem sleep enhancement in mouse. the present study used microinjection of neostigmine into pontine reticular formation of mouse to test the hypothesis that enhancing pontine cholinergic neurotransmission would cause increased rem ... | 2002 | 12489888 |
| 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) p ... | 2003 | 12654331 |
| orexin excites gabaergic neurons of the arcuate nucleus by activating the sodium--calcium exchanger. | the neuropeptides orexins/hypocretins are essential for normal wakefulness and energy balance, and disruption of their function causes narcolepsy and obesity. although much is known of the role of orexins in sleep/wake behavior, it remains unclear how they stimulate feeding and metabolism. one of the main targets of orexinergic neurons is the arcuate nucleus (arc) of the hypothalamus, which plays a key role in feeding and energy homeostasis. by combining patch-clamp and rt-multiplex pcr analysis ... | 2003 | 12832517 |
| manipulation of the endocannabinoid system by a general anaesthetic. | an article appearing in this issue of the british journal of pharmacology shows for the first time that the general anaesthetic propofol inhibits one of the enzymes catalysing endocannabinoid hydrolysis and inactivation, the fatty acid amide hydrolase, thereby enhancing the brain levels of anandamide and 2-arachidonoylglycerol in mouse brain. the authors provide evidence that this effect of propofol underlies part of the sedative effects of this compound. the importance of these findings in the ... | 2003 | 12839861 |
| sleep rhythmicity and homeostasis in mice with targeted disruption of mperiod genes. | in mammals, sleep is regulated by circadian and homeostatic mechanisms. the circadian component, residing in the suprachiasmatic nucleus (scn), regulates the timing of sleep, whereas homeostatic factors determine the amount of sleep. it is believed that these two processes regulating sleep are independent because sleep amount is unchanged after scn lesions. however, because such lesions necessarily damage neuronal connectivity, it is preferable to investigate this question in a genetic model tha ... | 2004 | 15031135 |
| sleep deprivation increases the activation of nuclear factor kappa b in lateral hypothalamic cells. | sleep deprivation increases sleep propensity in rats and mice as well as the production of several sleep-regulatory substances. nuclear factor kappa b (nf-kappa b) is a transcription factor implicated in the activation of many of these sleep-promoting substances. a unique population of neurons immunoreactive for the p65 subunit of nf-kappa b was previously localized within the caudal dorsolateral hypothalamus of rats. therefore, we evaluated the effect of sleep deprivation on nf-kappa bp65-immun ... | 2004 | 15033423 |
| polysomnography in transgenic hsod1 mice as down syndrome model. | sleep-wake homeostasis is crucial for behavioral performances and memory in the general population and in learning disability populations among them down syndrome patients. we investigated, in a mouse model of down syndrome, cortical eeg and sleep-wake architecture under baseline conditions and after a 4 hr sleep deprivation (sd). young heterozygous transgenic mice (s/+) for the human cu/zn superoxide dismutase (hsod-1) were obtained on fvb/n background. baseline records for slow wave sleep (sws ... | 2003 | 15068249 |
| sleep-wake architecture in mouse models for down syndrome. | sleep-wake homeostasis is crucial for behavioral performances and memory both in the general population and in patients with learning disability, among whom were down syndrome (ds) patients. we investigated, in mouse models of ds, cortical eeg and sleep-wake architecture under baseline conditions and after a 4-h sleep deprivation (sd). young hemizygous mice (hsodwt/+) transgenic for the human cuzn superoxide dismutase (hsod1) or for the human amyloid precursor protein (huapp(695); happwt/+) were ... | 2004 | 15193286 |
| altered sleep latency and arousal regulation in mice lacking norepinephrine. | latency to sleep and the amount of sensory stimulation required to awaken an animal are measures of arousal threshold, which are ultimately modulated by an arousal regulation system involving many brain areas. among these brain areas and network connections are wake-promoting nuclei of the brainstem and their corresponding neurotransmitters, including norepinephrine (ne). in this study, we used mice that are unable to produce ne to study its role in regulating sleep latency after a variety of in ... | 2004 | 15301933 |
| acute wake-promoting actions of jnj-5207852, a novel, diamine-based h3 antagonist. | 1 1-[4-(3-piperidin-1-yl-propoxy)-benzyl]-piperidine (jnj-5207852) is a novel, non-imidazole histamine h3 receptor antagonist, with high affinity at the rat (pki=8.9) and human (pki=9.24) h3 receptor. jnj-5207852 is selective for the h3 receptor, with negligible binding to other receptors, transporters and ion channels at 1 microm. 2 jnj-5207852 readily penetrates the brain tissue after subcutaneous (s.c.) administration, as determined by ex vivo autoradiography (ed50 of 0.13 mg kg(-1) in mice). ... | 2004 | 15466448 |
| c57bl/6j and b6.v-lepob mice differ in the cholinergic modulation of sleep and breathing. | respiratory and arousal state control are heritable traits in mice. b6.v-lep(ob) (ob) mice are leptin deficient and differ from c57bl/6j (b6) mice by a variation in the gene coding for leptin. the ob mouse has morbid obesity and disordered breathing that is homologous to breathing of obese humans. this study tested the hypothesis that microinjecting neostigmine into the pontine reticular nucleus, oral part (pno), of b6 and ob mice alters sleep and breathing. in b6 and ob mice, neostigmine caused ... | 2005 | 15475596 |
| abnormalities of social interactions and home-cage behavior in a mouse model of rett syndrome. | rett syndrome (rtt) is an autistic spectrum disorder with a known genetic basis. rtt is caused by loss of function mutations in the x-linked gene mecp2 and is characterized by loss of acquired motor, social and language skills in females beginning at 6-18 months of age. mecp2 mutations also cause non-syndromic mental retardation in males and females, and abnormalities of mecp2 expression in the brain have been found in autistic spectrum disorders. we studied home-cage behavior and social interac ... | 2005 | 15548546 |
| orexin neurons function in an efferent pathway of a food-entrainable circadian oscillator in eliciting food-anticipatory activity and wakefulness. | temporal restriction of feeding can entrain circadian behavioral and physiological rhythms in mammals. considering the critical functions of the hypothalamic orexin (hypocretin) neuropeptides in promoting wakefulness and locomotor activity, we examined the role of orexin neurons in the adaptation to restricted feeding. in orexin neuron-ablated transgenic mice, the food-entrained rhythmicity of mper2 expression in the brain and liver, the reversal of the sleep-wake cycle, and the recovery of dail ... | 2004 | 15548664 |
| reduced food anticipatory activity in genetically orexin (hypocretin) neuron-ablated mice. | daily restricted feeding (rf) produces an anticipatory locomotor activity rhythm and entrains the peripheral molecular oscillator independently of the central pacemaker located in the suprachiasmatic nucleus (scn). as orexins (hypocretins) are neuropeptides that coordinate sleep/wake patterns and motivated behaviours, such as food seeking, we studied the involvement of orexin in the food anticipatory activity (faa) induced by rf. daily rf shifted the mrna rhythm of a clock-controlled gene mdbp i ... | 2004 | 15579160 |
| sleep-wake behavior and responses of interleukin-6-deficient mice to sleep deprivation. | interleukin (il)-1 and tumor necrosis factor (tnf) are involved in the regulation of non-rapid eye movements sleep (nrems). accumulating evidence suggests il-6 modulates sleep under some pathophysiologic conditions. we used mice lacking a functional il-6 gene to investigate further a potential role for il-6 in the regulation of sleep. il-6 knockout mice (b6.129s6-il6tm1kopf; n=10) and c57bl/6j mice (n=10) were purchased from the jackson laboratory (bar harbor, me). twenty-four-hour baseline reco ... | 2005 | 15581736 |
| diurnal variation of lipopolysaccharide-induced alterations in sleep and body temperature of interleukin-6-deficient mice. | infectious challenge triggers a broad array of coordinated changes within the host organism, including alterations in sleep-wake behavior and body temperature. pro-inflammatory cytokines orchestrate many of the behavioral, metabolic, and endocrine responses to immune challenge. although interleukin (il)-6 mediates several aspects of sickness behavior, a role for this cytokine as a mediator of alterations in sleep in response to immune challenge has not been established. we evaluated sleep-wake b ... | 2005 | 15581737 |
| lack of delta waves and sleep disturbances during non-rapid eye movement sleep in mice lacking alpha1g-subunit of t-type calcium channels. | t-type calcium channels have been implicated as a pacemaker for brain rhythms during sleep but their contribution to behavioral states of sleep has been relatively uncertain. here, we found that mice lacking alpha1(g) t-type ca(2+) channels showed a loss of the thalamic delta (1-4 hz) waves and a reduction of sleep spindles (7-14 hz), whereas slow (<1 hz) rhythms were relatively intact, when compared with the wild-type during urethane anesthesia and non-rapid eye movement (nrem) sleep. analysis ... | 2004 | 15601764 |
| sleep and circadian abnormalities in a transgenic mouse model of alzheimer's disease: a role for cholinergic transmission. | the tg2576 mouse model of alzheimer's disease (ad) exhibits age-dependent amyloid beta (abeta) deposition in the brain. we studied electroencephalographically defined sleep and the circadian regulation of waking activities in tg2576 mice to determine whether these animals exhibit sleep abnormalities akin to those in ad. in tg2576 mice at all ages studied, the circadian period of wheel running rhythms in constant darkness was significantly longer than that of wild type mice. in addition, the incr ... | 2005 | 15708480 |
| assessment of modafinil on attentional processes in a five-choice serial reaction time test in the rat. | it is well known that modafinil is an effective wake-promoting agent, but there is growing evidence to suggest that modafinil may also enhance some aspects of cognition. in man, modafinil has been shown to enhance vigilance in sleep-deprived and/or narcoleptic subjects and also to improve executive-type functioning (predominantly inhibitory response control processes) across a variety of human patient population groups. preclinically, a delay-dependent improvement has been reported with modafini ... | 2005 | 15728436 |
| hearing in laboratory animals: strain differences and nonauditory effects of noise. | hearing in laboratory animals is a topic that traditionally has been the domain of the auditory researcher. however, hearing loss and exposure to various environmental sounds can lead to changes in multiple organ systems, making what laboratory animals hear of consequence for researchers beyond those solely interested in hearing. for example, several inbred mouse strains commonly used in biomedical research (e.g., c57bl/6, dba/2, and balb/c) experience a genetically determined, progressive heari ... | 2005 | 15766204 |
| sleep-wake states in transgenic mouse models overexpressing the human beta-amyloid precursor protein. | studies testing the amyloid hypothesis and recent advances in mouse molecular genetic technologies have played a critical role in improving our understanding of alzheimer's disease (ad). mouse models of ad currently available show only some of the characteristic neuropathology in human ad. studies have demonstrated, however, that these models are excellent tools for characterizing different aspects of the molecular pathology of ad and the neurobiological basis for the clinical heterogeneity in a ... | 2005 | 15844754 |
| nadph oxidase mediates hypersomnolence and brain oxidative injury in a murine model of sleep apnea. | persons with obstructive sleep apnea may have significant residual hypersomnolence, despite therapy. long-term hypoxia/reoxygenation events in adult mice, simulating oxygenation patterns of moderate-severe sleep apnea, result in lasting hypersomnolence, oxidative injury, and proinflammatory responses in wake-active brain regions. we hypothesized that long-term intermittent hypoxia activates brain nadph oxidase and that this enzyme serves as a critical source of superoxide in the oxidation injury ... | 2005 | 15994465 |
| the physiological role of orexins. | orexins/hypocretins are recently discovered neuropeptides synthetized mainly by neurons located in the posterolateral hypothalamus. hypocretin-1 and -2 are the same peptides as orexin-a and orexin-b. orexin a is a 33 amino acid peptide with n-terminal pyroglutamyl residue and two intrachain disulphide bonds. orexin b is a linear peptide of 28 amino acids. these two peptides are potent agonists at both the orexin-1 (oxr1) and orexin-2 (oxr2) receptors. orexin-a is selective ligand for oxr1 and ox ... | 2005 | 16135995 |
| the period length of fibroblast circadian gene expression varies widely among human individuals. | mammalian circadian behavior is governed by a central clock in the suprachiasmatic nucleus of the brain hypothalamus, and its intrinsic period length is believed to affect the phase of daily activities. measurement of this period length, normally accomplished by prolonged subject observation, is difficult and costly in humans. because a circadian clock similar to that of the suprachiasmatic nucleus is present in most cell types, we were able to engineer a lentiviral circadian reporter that permi ... | 2005 | 16167846 |
| deletion of the mammalian circadian clock gene bmal1/mop3 alters baseline sleep architecture and the response to sleep deprivation. | the finding that deletion or mutation of core circadian clock genes in both mice and flies induce unexpected alterations in sleep amount, sleep architecture and the recovery response to sleep deprivation, has led to new insights into functions of the circadian system that extend beyond its role as a regulator of the timing of the sleep-wake cycle. a key transcription factor in the transcriptional/translational feedback loop of mammalian circadian genes is bmal1/mop3, a heterodimeric partner to c ... | 2005 | 16171284 |
| impaired rapid eye movement sleep in the tg2576 app murine model of alzheimer's disease with injury to pedunculopontine cholinergic neurons. | impaired rapid eye movement sleep (rems) is commonly observed in alzheimer's disease, suggesting injury to mesopontine cholinergic neurons. we sought to determine whether abnormal beta-amyloid peptides impair rems and injure mesopontine cholinergic neurons in transgenic (happ695.swe) mice (tg2576) that model brain amyloid pathologies. tg2576 mice and wild-type littermates were studied at 2, 6, and 12 months by using sleep recordings, contextual fear conditioning, and immunohistochemistry. at 2 m ... | 2005 | 16251420 |
| gene expression in the rat brain during sleep deprivation and recovery sleep: an affymetrix genechip study. | previous studies have demonstrated that macromolecular synthesis in the brain is modulated in association with the occurrence of sleep and wakefulness. similarly, the spectral composition of electroencephalographic activity that occurs during sleep is dependent on the duration of prior wakefulness. since this homeostatic relationship between wake and sleep is highly conserved across mammalian species, genes that are truly involved in the electroencephalographic response to sleep deprivation migh ... | 2006 | 16257491 |
| histamine-immunoreactive neurons in the mouse and rat suprachiasmatic nucleus. | among the well-established roles of the neurotransmitter histamine (ha) is that as a regulator of the sleep-wake cycle, which early gained ha a reputation as a 'waking substance'. the tuberomammillary nucleus (tmn) of the posterior hypothalamus, which contains the sole source of neuronal ha in the brain, is reciprocally connected to the suprachiasmatic nucleus (scn) which, in turn, is best known as the pacemaker of circadian rhythms in mammals. we report ha-immunoreactive (-ir) neurons in the mo ... | 2005 | 16262638 |
| prokineticin 2 and circadian clock output. | circadian timing from the suprachiasmatic nucleus (scn) is a critical component of sleep regulation. animal lesion and genetic studies have indicated an essential interaction between the circadian signals and the homeostatic processes that regulate sleep. here we summarize the biological functions of prokineticins, a pair of newly discovered regulatory proteins, with focus on the circadian function of prokineticin 2 (pk2) and its potential role in sleep-wake regulation. pk2 has been shown as a c ... | 2005 | 16279936 |
| glucose-sensing neurons of the hypothalamus. | specialized subgroups of hypothalamic neurons exhibit specific excitatory or inhibitory electrical responses to changes in extracellular levels of glucose. glucose-excited neurons were traditionally assumed to employ a 'beta-cell' glucose-sensing strategy, where glucose elevates cytosolic atp, which closes katp channels containing kir6.2 subunits, causing depolarization and increased excitability. recent findings indicate that although elements of this canonical model are functional in some hypo ... | 2005 | 16321792 |
| novel seizure phenotype and sleep disruptions in knock-in mice with hypersensitive alpha 4* nicotinic receptors. | a leucine to alanine substitution (l9'a) was introduced in the m2 region of the mouse alpha4 neuronal nicotinic acetylcholine receptor (nachr) subunit. expressed in xenopus oocytes, alpha4(l9'a)beta2 nachrs were > or =30-fold more sensitive than wild type (wt) to both ach and nicotine. we generated knock-in mice with the l9'a mutation and studied their cellular responses, seizure phenotype, and sleep-wake cycle. seizure studies on alpha4-mutated animals are relevant to epilepsy research because ... | 2005 | 16339034 |
| the contribution of twik-related acid-sensitive k+-containing channels to the function of dorsal lateral geniculate thalamocortical relay neurons. | a genetic knockout was used to determine the specific contribution of twik-related acid-sensitive k+ (task)-1 channels to the function of dorsal lateral geniculate nucleus (dlg) thalamocortical relay (tc) neurons. disruption of task-1 function produced an approximately 19% decrease in amplitude of the standing outward current (iso) and a 3 +/- 1-mv depolarizing shift in resting membrane potential (vrest) of dlg neurons. we estimated that current through task-1 homodimers or task-1/task-3 heterod ... | 2006 | 16424077 |
| kv3 potassium channels control the duration of different arousal states by distinct stochastic and clock-like mechanisms. | sleep-wake behavior is tightly controlled in many animal species, suggesting genetically encoded, homeostatic control mechanisms that determine arousal-state dynamics. we reported that two voltage-gated potassium channels, kv3.1 and kv3.3, control sleep in wild-type and kv3-mutant mice. compared with wild-type (wt), homozygous double mutants (dko) that lack these channels sleep 40% less in the light and 22% less in the dark. to understand how the lack of these channels affects sleep, we analysed ... | 2006 | 16553620 |
| npas2 as a transcriptional regulator of non-rapid eye movement sleep: genotype and sex interactions. | because the transcription factor neuronal per-arnt-sim-type signal-sensor protein-domain protein 2 (npas2) acts both as a sensor and an effector of intracellular energy balance, and because sleep is thought to correct an energy imbalance incurred during waking, we examined npas2's role in sleep homeostasis using npas2 knockout (npas2-/-) mice. we found that, under conditions of increased sleep need, i.e., at the end of the active period or after sleep deprivation (sd), npas2 allows for sleep to ... | 2006 | 16636276 |
| disruptions in sleep time and sleep architecture in a mouse model of repeated ethanol withdrawal. | insomnia and other sleep difficulties are perhaps the most common and enduring symptoms reported by alcoholics undergoing detoxification, especially those alcoholics with a history of multiple detoxifications. while some studies have reported sleep disruptions in animal models after chronic ethanol exposure, the reports are inconsistent and few address sleep architecture across repeated ethanol exposures and withdrawals. the present study evaluated sleep time and architecture in a well-character ... | 2006 | 16792570 |
| an opposite role for tau in circadian rhythms revealed by mathematical modeling. | biological clocks with a period of approximately 24 h (circadian) exist in most organisms and time a variety of functions, including sleep-wake cycles, hormone release, bioluminescence, and core body temperature fluctuations. much of our understanding of the clock mechanism comes from the identification of specific mutations that affect circadian behavior. a widely studied mutation in casein kinase i (cki), the ckiepsilon(tau) mutant, has been shown to cause a loss of kinase function in vitro, b ... | 2006 | 16818876 |
| neuronal activity of histaminergic tuberomammillary neurons during wake-sleep states in the mouse. | using extracellular single-unit recordings alone and in combination with neurobiotin juxtacellular labeling and histamine immunohistochemistry, we have identified, for the first time in nonanesthetized, head-restrained mice, histamine neurons in the tuberomammillary nuclei of the posterior hypothalamus. they are all characterized by triphasic broad action potentials. they are active only during wakefulness, and their activity is related to a high level of vigilance. during waking states, they di ... | 2006 | 17021184 |
| sex differences in sleep: the response to sleep deprivation and restraint stress in mice. | numerous clinical studies and sleep surveys have shown pronounced sex differences in the occurrence of insomnia and other sleep pathologies. it has been suggested that sex differences in sleep, while subtle under baseline conditions, may increase in magnitude under biological or environmental challenges. however, controlled and experimental studies on sleep under challenged conditions rarely include female subjects. in this context, we examined sex differences in sleep in the mouse, not only und ... | 2006 | 17040010 |
| attenuated circadian rhythms in mice lacking the prokineticin 2 gene. | circadian clocks drive daily rhythms in virtually all organisms. in mammals, the suprachiasmatic nucleus (scn) is recognized as the master clock that synchronizes central and peripheral oscillators to evoke circadian rhythms of diverse physiology and behavior. how the timing information is transmitted from the scn clock to generate overt circadian rhythms is essentially unknown. prokineticin 2 (pk2), a clock-controlled gene that encodes a secreted protein, has been indicated as a candidate scn c ... | 2006 | 17093083 |
| differential target-dependent actions of coexpressed inhibitory dynorphin and excitatory hypocretin/orexin neuropeptides. | the hypocretin/orexin arousal system plays a key role in maintaining an alert wake state. the hypocretin peptide is colocalized with an opioid peptide, dynorphin. as dynorphin may be coreleased with hypocretin, we asked what action simultaneous stimulation with the excitatory neuropeptide hypocretin and the inhibitory peptide dynorphin might exert on cells postsynaptic to hypocretin axons, including hypocretin neurons. hypocretin neurons received direct synaptic contact from other hypocretin neu ... | 2006 | 17167093 |
| animal models of human placentation--a review. | this review examines the strengths and weaknesses of animal models of human placentation and pays particular attention to the mouse and non-human primates. analogies can be drawn between mouse and human in placental cell types and genes controlling placental development. there are, however, substantive differences, including a different mode of implantation, a prominent yolk sac placenta, and fewer placental hormones in the mouse. crucially, trophoblast invasion is very limited in the mouse and ... | 2007 | 17196252 |
| propionate increases neuronal histone acetylation, but is metabolized oxidatively by glia. relevance for propionic acidemia. | in propionic acidemia, propionate acts as a metabolic toxin in liver cells by accumulating in mitochondria as propionyl-coa and its derivative, methylcitrate, two tricarboxylic acid cycle inhibitors. little is known about the cerebral metabolism of propionate, although clinical effects of propionic acidemia are largely neurological. we found that propionate was metabolized oxidatively by glia: [3-(14)c]propionate injected into mouse striatum or cortex, gave a specific activity of glutamine that ... | 2007 | 17286595 |
| the brain h3-receptor as a novel therapeutic target for vigilance and sleep-wake disorders. | brain histaminergic neurons play a prominent role in arousal and maintenance of wakefulness (w). h(3)-receptors control the activity of histaminergic neurons through presynaptic autoinhibition. the role of h(3)-receptor antagonists/inverse agonists (h(3)r-antagonists) in the potential therapy of vigilance deficiency and sleep-wake disorders were studied by assessing their effects on the mouse cortical eeg and sleep-wake cycle in comparison to modafinil and classical psychostimulants. the h(3)r-a ... | 2007 | 17288995 |
| neurofibromatosis 1 and neurofibromatosis 2: a twenty first century perspective. | historically, neurofibromatosis 1 (nf1) has been inextricably linked with neurofibromatosis 2 (nf2). both are inherited autosomal-dominant neurocutaneous disorders that have high de novo mutation rates and carry a high risk of tumour formation. however, they are clinically and genetically distinct diseases and should be considered as seperate entities. nf1 is a common disease that mainly affects the skin and peripheral nervous system and causes characteristic bony dysplasia. by contrast, nf2 is ... | 2007 | 17362838 |
| sleep/wake fragmentation disrupts metabolism in a mouse model of narcolepsy. | recent population studies have identified important interrelationships between sleep duration and body weight regulation. the hypothalamic hypocretin/orexin neuropeptide system is able to influence each of these. disruption of the hypocretin system, such as occurs in narcolepsy, leads to a disruption of sleep and is often associated with increased body mass index. we examined the potential interrelationship between the hypocretin system, metabolism and sleep by measuring locomotion, feeding, dri ... | 2007 | 17379635 |
| mathematical model of network dynamics governing mouse sleep-wake behavior. | recent work in experimental neurophysiology has identified distinct neuronal populations in the rodent brain stem and hypothalamus that selectively promote wake and sleep. mutual inhibition between these cell groups has suggested the conceptual model of a sleep-wake switch that controls transitions between wake and sleep while minimizing time spent in intermediate states. by combining wake- and sleep-active populations with populations governing transitions between different stages of sleep, a " ... | 2007 | 17409167 |
| altered circadian and homeostatic sleep regulation in prokineticin 2-deficient mice. | sleep is regulated by circadian and homeostatic processes. recent studies with mutant mice have indicated that circadian-related genes regulate sleep amount, as well as the timing of sleep. thus a direct link between circadian and homeostatic regulation of sleep may exist, at least at the molecular level. prokineticin 2 (pk2), which oscillates daily with high amplitude in the suprachiasmatic nuclei (scn), has been postulated to be an scn output molecule. in particular, mice lacking the pk2 gene ... | 2007 | 17425220 |
| constant light housing during nursing causes human dsps (delayed sleep phase syndrome) behaviour in clock-mutant mice. | delayed sleep phase syndrome (dsps) is very often seen among patients with sleep-wake rhythm disorders. humans with the 3111c allele of the human clock gene tend to demonstrate a higher evening preference on the morningness-eveningness (me) preference test. dsps is thought to be an extreme form of this evening preference. clock-mutant mice have been proposed as an animal model of evening preference. in this study, we looked at whether constant light (ll) housing of clock-mutant mice during lacta ... | 2007 | 17445238 |
| clinical and neurobiological aspects of narcolepsy. | narcolepsy is characterized by excessive daytime sleepiness (eds), cataplexy and/or other dissociated manifestations of rapid eye movement (rem) sleep (hypnagogic hallucinations and sleep paralysis). narcolepsy is currently treated with amphetamine-like central nervous system (cns) stimulants (for eds) and antidepressants (for cataplexy). some other classes of compounds such as modafinil (a non-amphetamine wake-promoting compound for eds) and gamma-hydroxybutyrate (ghb, a short-acting sedative f ... | 2007 | 17470414 |
| the brain 5-ht1a receptor gene expression in hibernation. | hibernation is a unique physiological state characterized by profound reversible sleep-like state, depression in body temperature and metabolism. the serotonin 5-hydroxytryptamine(1a) (5-ht(1a)) receptor gene sequence in typical seasonal hibernator, ground squirrel (spermophilus undulatus), was specified. it was found that the fragment encoding the fifth transmembrane domain showed 93.6% of homology with the analogous fragment of the mouse and rat genes and displayed 88.5% homology with the huma ... | 2008 | 17711450 |
| pharmacological characterization of jnj-28583867, a histamine h(3) receptor antagonist and serotonin reuptake inhibitor. | wake-promoting agents such as modafinil are used in the clinic as adjuncts to antidepressant therapy in order to alleviate lethargy. the wake-promoting action of histamine h(3) receptor antagonists has been evidenced in numerous animal studies. they may therefore be a viable strategy for use as an antidepressant therapy in conjunction with selective serotonin reuptake inhibitors. jnj-28583867 (2-methyl-4-(4-methylsulfanyl-phenyl)-7-(3-morpholin-4-yl-propoxy)-1,2,3,4-tetrahydro-isoquinoline) is a ... | 2007 | 17765221 |
| a novel quantitative trait locus on mouse chromosome 18, "era1," modifies the entrainment of circadian rhythms. | the mammalian circadian clock in the suprachiasmatic nuclei (scn) of the hypothalamus conveys 24-h rhythmicity to sleep-wake cycles, locomotor activity, and other behavioral and physiological processes. the timing of rhythms relative to the light/dark (ld12:12) cycle is influenced in part by the endogenous circadian period and the time of day specific sensitivity of the clock to light. we now describe a novel circadian rhythm phenotype, and a locus influencing that phenotype, in a segregating po ... | 2007 | 17969459 |
| the postacrosomal assembly of sperm head protein, pawp, is independent of acrosome formation and dependent on microtubular manchette transport. | pawp (postacrosomal sheath ww domain-binding protein) exclusively resides in the postacrosomal sheath (pas) of the sperm perinuclear theca (pt). because of the importance of this region in initiating oocyte activation during mammalian fertilization [sutovsky, p., manandhar, g., wu, a., oko, r., 2003. interactions of sperm perinuclear theca with the oocyte: implications for oocyte activation, anti-polyspermy defense, and assisted reproduction. microsc. res. tech. 61, 362-378; wu, a., sutovsky, p. ... | 2007 | 17988661 |
| genome-wide expression profiling and bioinformatics analysis of diurnally regulated genes in the mouse prefrontal cortex. | the prefrontal cortex is important in regulating sleep and mood. diurnally regulated genes in the prefrontal cortex may be controlled by the circadian system, by sleep:wake states, or by cellular metabolism or environmental responses. bioinformatics analysis of these genes will provide insights into a wide-range of pathways that are involved in the pathophysiology of sleep disorders and psychiatric disorders with sleep disturbances. | 2007 | 18028544 |
| prolonged wakefulness induces experience-dependent synaptic plasticity in mouse hypocretin/orexin neurons. | sleep is a natural process that preserves energy, facilitates development, and restores the nervous system in higher animals. sleep loss resulting from physiological and pathological conditions exerts tremendous pressure on neuronal circuitry responsible for sleep-wake regulation. it is not yet clear how acute and chronic sleep loss modify neuronal activities and lead to adaptive changes in animals. here, we show that acute and chronic prolonged wakefulness in mice induced by modafinil treatment ... | 2007 | 18060037 |
| homer1a is a core brain molecular correlate of sleep loss. | sleep is regulated by a homeostatic process that determines its need and by a circadian process that determines its timing. by using sleep deprivation and transcriptome profiling in inbred mouse strains, we show that genetic background affects susceptibility to sleep loss at the transcriptional level in a tissue-dependent manner. in the brain, homer1a expression best reflects the response to sleep loss. time-course gene expression analysis suggests that 2,032 brain transcripts are under circadia ... | 2007 | 18077435 |
| effects of serotonergic activation by 5-hydroxytryptophan on sleep and body temperature of c57bl/6j and interleukin-6-deficient mice are dose and time related. | extensive data implicate serotonin (5-hydroxytryptamine [5-ht]) in the regulation of sleep. jouvet has hypothesized that 5-ht promotes wakefulness, yet is necessary for subsequent non-rapid eye movement (nrem) sleep, actions he proposes to be mediated by sleep factors. studies in rat support this dual role for 5-ht. the objectives of this study were to (1) determine effects of serotonergic activation on sleep of mice and (2) elucidate a potential role for the cytokine interleukin-6 as a sleep fa ... | 2008 | 18220075 |
| sleep and eeg features in genetic models of down syndrome. | down syndrome is characterized by a host of behavioral abnormalities including sleep disturbances. sleep and eeg was studied at the age of 3 months in two mouse models of the condition, ts65dn and ts1cje, carrying one extra copy of partially overlapping segments of the mmu chromosome 16 (equivalent to the human chromosome 21). we found that the ts65dn mice showed increased waking amounts at the expense of non-rem sleep, increased theta power during sleep and a delayed sleep rebound after sleep d ... | 2008 | 18282758 |
| modulatory effects of 5-fluorouracil on the rhythmic expression of circadian clock genes: a possible mechanism of chemotherapy-induced circadian rhythm disturbances. | the circadian clock system is necessary to adapt endogenous physiological functions to daily variations in environmental conditions. abnormality in circadian rhythms, such as the sleep-wake cycle and the timing of hormonal secretions, is implicated in various physiological and psychiatrical disorders. recent molecular studies have revealed that oscillation in the transcription of specific clock genes plays a central role in the generation of 24h cycles of physiology and behavior. it has been not ... | 2008 | 18329632 |
| effects of i.c.v. administration of interleukin-1 on sleep and body temperature of interleukin-6-deficient mice. | cytokines in brain contribute to the regulation of physiological processes and complex behavior, including sleep. the cytokines that have been most extensively studied with respect to sleep are interleukin (il)-1beta, tumor necrosis factor (tnf)-alpha, and il-6. administration of these cytokines into laboratory animals, or in some cases into healthy human volunteers, increases the amount of time spent in non-rapid eye movement (nrem) sleep. although antagonizing the il-1 or tnf systems reduces t ... | 2008 | 18367337 |
| sleep architecture of the melanin-concentrating hormone receptor 1-knockout mice. | growing amounts of data indicate involvement of the posterior hypothalamus in the regulation of sleep, especially paradoxical sleep (ps). accordingly, we previously showed that the melanin-concentrating hormone (mch)-producing neurons of the rat hypothalamus are selectively activated during a ps rebound. in addition, intracerebroventricular infusion of mch increases total sleep duration, suggesting a new role for mch in sleep regulation. to determine whether activation of the mch system promotes ... | 2008 | 18380672 |
| delayed orexin signaling consolidates wakefulness and sleep: physiology and modeling. | orexin-producing neurons are clearly essential for the regulation of wakefulness and sleep because loss of these cells produces narcolepsy. however, little is understood about how these neurons dynamically interact with other wake- and sleep-regulatory nuclei to control behavioral states. using survival analysis of wake bouts in wild-type and orexin knockout mice, we found that orexins are necessary for the maintenance of long bouts of wakefulness, but orexin deficiency has little impact on wake ... | 2008 | 18417630 |
| neuronal activity of orexin and non-orexin waking-active neurons during wake-sleep states in the mouse. | using extracellular single unit recordings alone or in combination with neurobiotin juxtacellular labeling and orexin (hypocretin) immunohistochemistry in the mouse, we have recorded a total of 452 neurons in the orexin neuron field of the posterior hypothalamus. of these, 76 exhibited tonic discharge highly specific to wakefulness, referred to as waking-active neurons. they showed differences from each other in terms of spike shape, activity profile, and response to an arousing sound stimulus a ... | 2008 | 18424001 |
| modeling the circadian clock: from molecular mechanism to physiological disorders. | based on genetic and biochemical advances on the molecular mechanism of circadian rhythms, a computational model for the mammalian circadian clock is used to examine the dynamical bases of circadian-clock-related physiological disorders in humans. entrainment by the light-dark cycle with a phase advance or a phase delay is associated with the familial advanced sleep phase syndrome (fasps) or the delayed sleep phase syndrome (dsps), respectively. lack of entrainment corresponding to the occurrenc ... | 2008 | 18478538 |
| decline of the presynaptic network, including gabaergic terminals, in the aging suprachiasmatic nucleus of the mouse. | biological rhythms, and especially the sleep/wake cycle, are frequently disrupted during senescence. this draws attention to the study of aging-related changes in the hypothalamic suprachiasmatic nucleus (scn), the master circadian pacemaker. the authors here compared the scn of young and old mice, analyzing presynaptic terminals, including the gamma-aminobutyric acid (gaba)ergic network, and molecules related to the regulation of gaba, the main neurotransmitter of scn neurons. transcripts of th ... | 2008 | 18487414 |
| ablation of kv3.1 and kv3.3 potassium channels disrupts thalamocortical oscillations in vitro and in vivo. | the genes kcnc1 and kcnc3 encode the subunits for the fast-activating/fast-deactivating, voltage-gated potassium channels kv3.1 and kv3.3, which are expressed in several brain regions known to be involved in the regulation of the sleep-wake cycle. when these genes are genetically eliminated, kv3.1/kv3.3-deficient mice display severe sleep loss as a result of unstable slow-wave sleep. within the thalamocortical circuitry, kv3.1 and kv3.3 subunits are highly expressed in the thalamic reticular nuc ... | 2008 | 18495891 |
| when clocks go bad: neurobehavioural consequences of disrupted circadian timing. | progress in unravelling the cellular and molecular basis of mammalian circadian regulation over the past decade has provided us with new avenues through which we can explore central nervous system disease. deteriorations in measurable circadian output parameters, such as sleep/wake deficits and dysregulation of circulating hormone levels, are common features of most central nervous system disorders. at the core of the mammalian circadian system is a complex of molecular oscillations within the h ... | 2008 | 18516223 |
| sleep deprivation effects on circadian clock gene expression in the cerebral cortex parallel electroencephalographic differences among mouse strains. | sleep deprivation (sd) results in increased electroencephalographic (eeg) delta power during subsequent non-rapid eye movement sleep (nrems) and is associated with changes in the expression of circadian clock-related genes in the cerebral cortex. the increase of nrems delta power as a function of previous wake duration varies among inbred mouse strains. we sought to determine whether sd-dependent changes in circadian clock gene expression parallel this strain difference described previously at t ... | 2008 | 18614689 |
| adenosine as an endogenous regulating factor of hippocampal sharp waves. | the rodent hippocampus exhibits population activities called sharp waves (spws) during slow wave sleep and wake immobility. spws are important for hippocampal-cortical communication and memory consolidation, and abnormal sharp wave-ripple complexes are closely related to epileptic seizures. although the spws are known to arise from the ca3 circuit, the local mechanisms underlying their generation are not fully understood. we hypothesize that endogenous adenosine is a local regulator of hippocamp ... | 2009 | 18785213 |
| high-fat diet delays and fasting advances the circadian expression of adiponectin signaling components in mouse liver. | the circadian clock controls energy homeostasis by regulating circadian expression and/or activity of enzymes involved in metabolism. disruption of circadian rhythms may lead to obesity and metabolic disorders. we tested whether the biological clock controls adiponectin signaling pathway in the liver and whether fasting and/or high-fat (hf) diet affects this control. mice were fed low-fat or hf diet and fasted on the last day. the circadian expression of clock genes and components of adiponectin ... | 2009 | 18801899 |
| differential entrainment of a social rhythm in adolescent mice. | daily routines in animal activities range from sleep-wake cycles, to foraging bouts, to social interactions. among animals living within groups, it is unclear whether the motivations that underlie social interactions respond to daily light-dark (ld) cycles or endogenous circadian rhythms. employing two mouse strains (balb/cj [balb] and c57bl/6j [b6]) with genetically based differences in social affect and circadian rhythms, we examined how social investigation (si) is modulated by social depriva ... | 2008 | 18840476 |
| sleep-wake regulation is altered in leptin-resistant (db/db) genetically obese and diabetic mice. | recent epidemiological and clinical studies indicate that the control of sleep-wake states may be an important factor in the regulation of energy metabolism. leptin is a peripherally synthesized hormone that has critical signaling properties in the brain for the control of long-term energy homeostasis. in this study, we examined the hypothesis that leptin signaling exerts a role in sleep-wake regulation and that leptin may represent an important mechanistic link in the coordination of sleep-wake ... | 2008 | 18843095 |
| orexin (hypocretin) gene transfer diminishes narcoleptic sleep behavior in mice. | gene transfer has proven to be an effective neurobiological tool in a number of neurodegenerative diseases, but it is not known if it can correct a sleep disorder. narcolepsy is a neurodegenerative sleep disorder linked to the loss of neurons containing the neuropeptide orexin, also known as hypocretin. here, a replication-defective herpes simplex virus-1 amplicon-based vector was constructed to transfer the gene for mouse prepro-orexin into mice with a genetic deletion of the orexin gene. after ... | 2008 | 18973565 |