Lighting conditions alter Candida albicans-induced sleep responses in rabbits

To evaluate the influence of light on sleep patterns after microbial challenge, we studied rabbits housed in 12:12-h light-dark (LD), constant light (LL), or constant darkness (DD) before and after intravenous Candida albicans inoculation. Compared with the LD group, uninoculated LL rabbits sporadically increased slow-wave sleep and delta-wave amplitudes during the circadian period previously associated with the dark phase. In contrast, uninfected DD rabbits showed reduced sleep during the circadian period previously associated with the light phase. Inoculation of LD rabbits with Candida approximately 2 h after light onset increased slow-wave sleep and delta-wave amplitudes during hours 4-8 postinoculation and reduced these parameters during hours 20-46. In contrast, Candida-inoculated LL rabbits demonstrated increased slow-wave sleep for up to 28 h after inoculation, with little subsequent reduction; delta-wave amplitudes were similar to those of LD rabbits. Candida-inoculated DD rabbits demonstrated attenuated increases in slow-wave sleep and delta-wave amplitudes, but the suppression phase was not altered. We conclude that lighting conditions modulate microbially induced sleep alterations.

Download Full-text

Enhancement of quiet sleep in rabbit neonates by muramyl dipeptide

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1987.253.4.r646 ◽

1987 ◽

Vol 253 (4) ◽

pp. R646-R654 ◽

Cited By ~ 4

Author(s):

D. Davenne ◽

J. M. Krueger

Keyword(s):

Slow Wave ◽

Slow Wave Sleep ◽

Muramyl Dipeptide ◽

Wave Activity ◽

Synthetic Analogue ◽

Active Sleep ◽

Quiet Sleep ◽

Delta Wave ◽

Parallel Increase ◽

Behavioral Criteria

Muramyl peptides that induce excess slow-wave sleep have been isolated from urine and brain. A synthetic analogue to those substances, muramyl dipeptide (MDP, N-acetylmuramyl-L-alanyl-D-isoglutamine), was found to induce prolonged increases in slow-wave sleep and to increase electroencephalographic (EEG) delta-wave activity. MDP is also pyrogenic, although this activity can be separated from its somnogenic activity. To further investigate the somnogenic actions of MDP, neonatal rabbits were used in the present study. Intraperitoneal injection of 100 micrograms/kg MDP induced differential somnogenic and pyrogenic effects; from postnatal days 7-9, MDP increased duration of quiet sleep (QS, the precursor of adult slow-wave sleep) and decreased active sleep (AS) as judged by behavioral criteria. These animals were not febrile during the period of enhanced QS, nor did MDP alter EEG delta-wave activity at this age. From postnatal days 10-15, MDP induced prolonged (6 h) increases in duration of QS; both behavioral and EEG criteria were used at this age to determine duration of QS and AS. Maximum MDP-induced effects occurred during the 2nd h, with a parallel increase in amplitudes of EEG delta-wave activity. At this age, MDP also elicited monophasic fevers and inhibition of AS, with maximum effects observed during hours 3-4 postinjection. After postnatal day 16, MDP-induced somnogenic and febrile responses were similar to those observed in adult rabbits. We conclude that the mechanisms responsible for behavioral sleep states are responsive to a sleep-promoting substance early in ontogenesis.

Download Full-text

Somnogenic, pyrogenic, and hematologic effects of experimental pasteurellosis in rabbits

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1990.258.2.r536 ◽

1990 ◽

Vol 258 (2) ◽

pp. R536-R542 ◽

Cited By ~ 2

Author(s):

L. A. Toth ◽

J. M. Krueger

Keyword(s):

Slow Wave ◽

Pasteurella Multocida ◽

Slow Wave Sleep ◽

Time Dependent ◽

Rapid Eye Movement Sleep ◽

Bacterial Challenge ◽

Intranasal Inoculation ◽

Routes Of Administration ◽

Sleep Alterations ◽

Intravenous Inoculation

Previous work has demonstrated that intravenous inoculation of rabbits with various microorganisms induces complex time-dependent alterations in sleep as well as other pathophysiological effects typically associated with infectious disease. To evaluate the effects of bacterial challenge that more closely resembles naturally developing disease, we inoculated rabbits with Pasteurella multocida, a common pathogen of this species, using routes of administration that mimic normal routes of exposure. Biphasic sleep alterations characterized initially by enhanced slow-wave sleep and later by decreased slow-wave sleep occurred after intravenous, intramuscular, subcutaneous, or intranasal inoculation. Rapid-eye-movement sleep was inhibited for most of the 48-h period after inoculation. Inoculation by all four routes also induced fever and qualitatively similar hematologic changes. However, the magnitude and specific temporal patterns of both somnogenic changes and other pathophysiological effects varied with the route of inoculation.

Download Full-text

Modulation of sleep by cortisone in normal and bacterially infected rabbits

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1992.263.6.r1339 ◽

1992 ◽

Vol 263 (6) ◽

pp. R1339-R1346

Author(s):

L. A. Toth ◽

T. W. Gardiner ◽

J. M. Krueger

Keyword(s):

Infectious Disease ◽

Slow Wave ◽

Slow Wave Sleep ◽

Initial Increase ◽

Sleep Patterns ◽

Immune Modulators ◽

E Coli ◽

Subsequent Decrease ◽

Before And After ◽

Microbial Infections

Infectious disease is known to alter both sleep patterns and hydrocortisone (cortisol) concentrations in rabbits. Moreover, the sleep-altering effects of microbial infections are likely to be mediated via endogenous immune modulators whose actions are attenuated by glucocorticoids. To evaluate the relationships between sleep and glucocorticoids during infectious disease, the effects of cortisone administration (20 mg/kg, im) on sleep were examined before and after inoculation of rabbits with Staphylococcus aureus or Escherichia coli. When administered alone, cortisone did not alter the amount of time spent in slow-wave sleep (SWS) but did reduce electroencephalographic (EEG) slow-wave amplitudes during SWS, the number of bouts of SWS and the amount of time spent in rapid-eye-movement sleep. The duration of individual bouts of SWS was increased after cortisone treatment. Bacterially infected rabbits developed biphasic changes in sleep patterns that were characterized by an initial increase and a subsequent decrease both in SWS time and in EEG slow-wave amplitudes during sleep. Cortisone treatment attenuated these effects in S. aureus-inoculated rabbits. In contrast, cortisone treatment did not alter the initial phase of enhanced sleep in E. coli-inoculated rabbits but did attenuate the subsequent sleep suppression. These data indicate that glucocorticoid administration is associated with an attenuated sleep response in bacterially inoculated rabbits.

Download Full-text

Budgerigars have complex sleep structure similar to that of mammals

PLoS Biology ◽

10.1371/journal.pbio.3000929 ◽

2020 ◽

Vol 18 (11) ◽

pp. e3000929

Author(s):

Sofija V. Canavan ◽

Daniel Margoliash

Keyword(s):

Slow Wave ◽

Slow Wave Sleep ◽

Mammalian Species ◽

Parallel Evolution ◽

Bird Species ◽

Sleep Architecture ◽

Sleep Structure ◽

Lighting Conditions ◽

Order Of Magnitude ◽

Electroencephalogram Eeg

Birds and mammals share specialized forms of sleep including slow wave sleep (SWS) and rapid eye movement sleep (REM), raising the question of why and how specialized sleep evolved. Extensive prior studies concluded that avian sleep lacked many features characteristic of mammalian sleep, and therefore that specialized sleep must have evolved independently in birds and mammals. This has been challenged by evidence of more complex sleep in multiple songbird species. To extend this analysis beyond songbirds, we examined a species of parrot, the sister taxon to songbirds. We implanted adult budgerigars (Melopsittacus undulatus) with electroencephalogram (EEG) and electrooculogram (EOG) electrodes to evaluate sleep architecture, and video monitored birds during sleep. Sleep was scored with manual and automated techniques, including automated detection of slow waves and eye movements. This can help define a new standard for how to score sleep in birds. Budgerigars exhibited consolidated sleep, a pattern also observed in songbirds, and many mammalian species, including humans. We found that REM constituted 26.5% of total sleep, comparable to humans and an order of magnitude greater than previously reported. Although we observed no spindles, we found a clear state of intermediate sleep (IS) similar to non-REM (NREM) stage 2. Across the night, SWS decreased and REM increased, as observed in mammals and songbirds. Slow wave activity (SWA) fluctuated with a 29-min ultradian rhythm, indicating a tendency to move systematically through sleep states as observed in other species with consolidated sleep. These results are at variance with numerous older sleep studies, including for budgerigars. Here, we demonstrated that lighting conditions used in the prior budgerigar study—and commonly used in older bird studies—dramatically disrupted budgerigar sleep structure, explaining the prior results. Thus, it is likely that more complex sleep has been overlooked in a broad range of bird species. The similarities in sleep architecture observed in mammals, songbirds, and now budgerigars, alongside recent work in reptiles and basal birds, provide support for the hypothesis that a common amniote ancestor possessed the precursors that gave rise to REM and SWS at one or more loci in the parallel evolution of sleep in higher vertebrates. We discuss this hypothesis in terms of the common plan of forebrain organization shared by reptiles, birds, and mammals.

Download Full-text

The influence of lighting conditions upon the level and course of increase in specific activity of serotonin N-acetyltransferase in the developing chick pineal gland

Canadian Journal of Biochemistry ◽

10.1139/o76-017 ◽

1976 ◽

Vol 54 (2) ◽

pp. 103-109 ◽

Cited By ~ 13

Author(s):

I. H. Fraser ◽

S. D. Wainwright

Keyword(s):

Pineal Gland ◽

Specific Activity ◽

Major Product ◽

Constant Darkness ◽

Dark Phase ◽

Light Phase ◽

Normal Cycle ◽

Lighting Conditions ◽

Hydroxyindoleacetic Acid ◽

Unidentified Metabolite

A diurnal cycle in level of serotonin acetyltransferase (acetyl-CoA: arylamine N-acetyltransferase (EC 2.3.1.5)) activity was found in the pineal gland of chicks aged 16 to 20 days maintained under diurnal lighting conditions. Diurnal variation in levels of activity was markedly reduced in the pineal gland of birds kept in constant darkness, and suppressed in the gland of chicks under constant illumination. High levels of activity attained during the dark phase of the normal cycle rapidly declined when the birds were transferred to the light. The light phase level of serotonin acetyltransferase of the pineal increased progressively from the 11th day of incubation to about 1 week post-hatch. This course of increase in enzyme activity was largely unaffected by lighting conditions. Under conditions for assay of serotonin acetyltransferase activity in the chick pineal gland and brain, radioactive serotonin gave rise to N-acetylserotonin, 5-hydroxyindoleacetic acid and a further unidentified metabolite, which was quantitatively the major product.

Download Full-text

Evidence That Homeostatic Sleep Regulation Depends on Ambient Lighting Conditions during Wakefulness

Clocks & Sleep ◽

10.3390/clockssleep1040040 ◽

2019 ◽

Vol 1 (4) ◽

pp. 517-531 ◽

Cited By ~ 5

Author(s):

Christian Cajochen ◽

Carolin Reichert ◽

Micheline Maire ◽

Luc J. M. Schlangen ◽

Christina Schmidt ◽

...

Keyword(s):

Slow Wave ◽

White Light ◽

Slow Wave Sleep ◽

Age Groups ◽

Sleep Regulation ◽

Older Volunteers ◽

Lighting Conditions ◽

Ambient Lighting ◽

Sleep Homeostasis ◽

Subjective Sleepiness

We examined whether ambient lighting conditions during extended wakefulness modulate the homeostatic response to sleep loss as indexed by. slow wave sleep (SWS) and electroencephalographic (EEG) slow-wave activity (SWA) in healthy young and older volunteers. Thirty-eight young and older participants underwent 40 hours of extended wakefulness [i.e., sleep deprivation (SD)] once under dim light (DL: 8 lux, 2800 K), and once under either white light (WL: 250 lux, 2800 K) or blue-enriched white light (BL: 250 lux, 9000 K) exposure. Subjective sleepiness was assessed hourly and polysomnography was quantified during the baseline night prior to the 40-h SD and during the subsequent recovery night. Both the young and older participants responded with a higher homeostatic sleep response to 40-h SD after WL and BL than after DL. This was indexed by a significantly faster intra-night accumulation of SWS and a significantly higher response in relative EEG SWA during the recovery night after WL and BL than after DL for both age groups. No significant differences were observed between the WL and BL condition for these two particular SWS and SWA measures. Subjective sleepiness ratings during the 40-h SD were significantly reduced under both WL and BL compared to DL, but were not significantly associated with markers of sleep homeostasis in both age groups. Our data indicate that not only the duration of prior wakefulness, but also the experienced illuminance during wakefulness affects homeostatic sleep regulation in humans. Thus, working extended hours under low illuminance may negatively impact subsequent sleep intensity in humans.

Download Full-text

Circasemidian 12 h cycle of slow wave sleep under constant darkness

Clinical Neurophysiology ◽

10.1016/s1388-2457(02)00168-2 ◽

2002 ◽

Vol 113 (9) ◽

pp. 1505-1516 ◽

Cited By ~ 16

Author(s):

Mitsuo Hayashi ◽

Toshio Morikawa ◽

Tadao Hori

Keyword(s):

Slow Wave ◽

Slow Wave Sleep ◽

Constant Darkness

Download Full-text

Sleep patterning changes in a prenatal stress model of depression

Journal of Developmental Origins of Health and Disease ◽

10.1017/s2040174417000642 ◽

2017 ◽

Vol 9 (1) ◽

pp. 102-111 ◽

Cited By ~ 3

Author(s):

H. M. Sickmann ◽

C. Skoven ◽

J. F. Bastlund ◽

T. B. Dyrby ◽

N. Plath ◽

...

Keyword(s):

Prenatal Stress ◽

Slow Wave Sleep ◽

Active Phase ◽

Female Rats ◽

Dark Phase ◽

Sprague Dawley ◽

Male And Female Rats ◽

Circadian Time ◽

Before And After ◽

In The Beginning

Clinical depression is accompanied by changes in sleep patterning, which is controlled in a circadian fashion. It is thus desirable that animal models of depression mirror such diurnally-specific state alterations, along with other behavioral and physiological changes. We previously found several changes in behavior indicative of a depression-like phenotype in offspring of rats subjected to repeated, variable prenatal stress (PNS), including increased locomotor activity during specific periods of the circadian cycle. We, therefore, investigated whether PNS rats also exhibit alterations in sleep/wakefulness behavior around the change from light-to-dark phase. Control and PNS Sprague–Dawley rats were implanted with electrodes for continuous monitoring of electroencephalic activity used to determine behavioral state. The distribution of slow-wave sleep (SWS), rapid eye movement sleep (REMS) and wakefulness was compared for periods before and after lights were turned off, between baseline conditions and after exposure to an acute stressor. Both REMS and SWS amounts were increased in PNS rats relative to control animals in the beginning of the dark phase. REMS changes were due to an increase in REMS bout number, rather than in bout duration. During this circadian time period, we did not find any sex differences in the state changes. These results indicate that PNS affects baseline sleep patterning in both male and female rats around active-phase onset.

Download Full-text