Immediate Early Gene Expression in Brain During Sleep Deprivation: Preliminary ObservationsO'Hara, Bruce, F.;Young, Kimberly, A.;Watson, Fiona, L.;Heller, H., Craig;Kilduff, Thomas, S.
doi: 10.1093/sleep/16.1.1pmid: 8456228
Summary: The two-process model of sleep regulation posits that a homeostatic drive to sleep, referred to as Process S, increases with time spent awake. The purpose of this study was to evaluate whether immediate early gene (IEG) expression increases in the brain in proportion to time spent awake, when Process S would be expected to increase. Rats were deprived of sleep by cage tapping, cage rotation and gentle handling beginning at light onset for 45 minutes, 3 hours or 6 hours. At the end of the deprivation periods, deprived animals and an equal number of controls were decapitated, the brains dissected into subregions and frozen. Northern blots were prepared from cortex, thalamus, cerebellum, pons and hypothalamus and hybridized with cDNA probes to five IEG mRNAs; c-fos, c-jun, junB, NGFI-A and NGFI-B. Basal levels of c-fos mRNA were detectable in all brain regions from all animals. Sleep-deprived animals showed higher expression of c-fos mRNA than control animals following 45 minutes and 6 hours of sleep deprivation in all brain regions examined, with the greatest increases observed in the cerebellum. Surprisingly, only the pons and cerebellum showed clear increases at the 3-hour timepoint. In contrast to c-fos, c-jun mRNA was essentially invariant among the animals while junB mRNA was inconsistently elevated. The expression of NGFI-A and NGFI-B was similar to the c-fos pattern but of lesser magnitude. These results suggest that a differential change in neuronal gene expression occurs in response to this mode of sleep deprivation, but cannot exclude the possibility that they represent a more generalized stress response. Sleep deprivation, Stress-c-fos-c-jun-junB-NGFI-A-NGFI-B This content is only available as a PDF. © 1993 American Sleep Disorders Association and Sleep Research Society
Effect of Specific Muscarinic M2 Receptor Antagonist on Carbachol Induced Long-Term REM SleepDatta,, Subimal;Quattrochi, James, J.;Hobson, J., Allan
doi: 10.1093/sleep/16.1.8pmid: N/A
Summary: Six cats were chronically implanted with a standard set of sleep-scoring electrodes and bilateral stainlesssteel guide tubes for microinjection of drugs in the peribrachial area (PBL). Pretreatment of drug injection sites in the PBL with the M2 antagonist methoctramine blocks both the immediate triggering of ponto-geniculo-occipital (PGO) waves and the later prolonged enhancement of REM sleep that is induced by carbachol. These results support the hypothesis that the carbachol effects are mediated via the M2 muscarinic receptor that is known to be present in the PBL. Long-term REM sleep, Ponto-geniculo-occipital waves, Carbachol, Methoctramine, M2 receptor, Peribrachial area This content is only available as a PDF.
The 5-HT2 Antagonist Ritanserin Decreases Sleep in CatsSommerfelt,, Liv;Ursin,, Reidun
doi: 10.1093/sleep/16.1.15pmid: 8456229
Summary: Sleep and wakefulness were recorded in cats after oral administration of the 5-HT2 antagonist ritanserin at doses of 0.5 and 1.0 mg/kg (n = 6), and after 2.5 mg/kg (n = 3). A subgroup (n = 4) of the animals also received the selective 5-HT uptake inhibitor zimeldine and a combination of ritanserin and zimeldine. The drugs were administered shortly after light onset, and sleep was recorded for 15 hours. Waking was increased and slow wave sleep (SWS), particularly deep slow wave sleep (SWS-2), was decreased throughout the recording time after ritanserin administration. Rapid eye movement (REM) sleep latency was increased, and the amount of REM sleep was reduced. In the combination study, ritanserin reduced the delayed SWS increase following the serotonin uptake inhibitor. The findings of increased waking and decreased SWS-2 after ritanserin in cats contrasts with findings from humans and rats where slow wave sleep is increased following ritanserin administration. Ritanserin, Zimeldine 5-HT2, Sleep, Cats This content is only available as a PDF. © 1993 American Sleep Disorders Association and Sleep Research Society
Minute-by-Minute Association of Heart Rate Variation with Basal Heart Rate in Developing InfantsSchechtman, Vicki, L.;Harper, Ronald, M.
doi: 10.1093/sleep/16.1.23pmid: 8456230
Summary: Particular types of heart rate variation are enhanced during periods of slow heart rate and diminished when heart rate is high. We examined how the correlations between heart rate and various types of heart rate variation developed in normal infants. Polygraphic recordings were obtained from 25 infants at 1 week and at 1, 2, 3, 4 and 6 months of age. Median heart rate and the extents of heart rate variation at three distinct frequencies were determined for each 1 -minute epoch. Pearson's r was used to assess the correlation of median heart rate in each epoch with each of three types of heart rate variation. For each recording, correlations were assessed separately for quiet sleep, rapid eye movement (REM) sleep and waking. The maturational patterns of heart rate by heart rate variation correlations were strongly influenced by sleep-waking state and were dissimilar to those previously reported for correlations between cardiac and respiratory measures. The findings suggest dissimilar developmental patterns for autonomic and somatic motor systems, and include a discontinuity in autonomic development at approximately 1 month of age. We speculate that these trends reflect a change in the nature of sleep states as forebrain connections develop. Heart rate, Heart rate variation, Infants, Respiratory sinus arrhythmia, Sleep This content is only available as a PDF. © 1993 American Sleep Disorders Association and Sleep Research Society
Snoring and Anxiety DreamsGroen, J. H. M., de;Velde, W. Op, den;Hovens, J., E.;Falger, P. R., J.;Schouten, E. G., W.;Duijn, H., van
doi: 10.1093/sleep/16.1.35pmid: N/A
Summary: In a group of elderly males who had been exposed to excessive stress during World War II, 56% of whom suffered from current post-traumatic stress disorder, a significant association was found between snoring and the occurrence of anxiety dreams, independent of the use of sedatives, antidepressants, smoking and alcohol and coffee consumption. Anxiety dream incidence was highest when snoring was accompanied by respiratory pauses. The underlying pathophysiologic mechanisms are thought to be hypercapnia and autonomic-vegetative arousal, resulting from obstructive sleep apneic episodes in heavy snoring. Polysomnographic sleep studies are needed to confirm this hypothesis. PTSD, Anxiety dreams, Snoring, Apnea This content is only available as a PDF.
Plasma Levels of Atrial Natriuretic Factor in Moderate to Severe Obstructive Sleep Apnea SyndromeLin,, Ching-Chi;Tsan,, Kun-Wu;Lin,, Ching-Yuang
doi: 10.1093/sleep/16.1.37pmid: 8456234
Summary: To evaluate atrial natriuretic factor (ANF) secretion during sleep in obstructive sleep apnea syndrome (OSAS), plasma ANF was measured every 3 hours before and after effective nasal continuous positive airway pressure (CPAP) treatment in 10 patients with moderate to severe OSAS and 10 normal subjects. The results showed daily changes in ANF levels in normal controls and in OSAS patients after effective therapy, with a nadir at 0300 hours and a peak at 2100 hours. There was no significant daily variation of ANF levels in patients with OSAS before therapy, and ANF levels from midnight to 0900 hours were significantly higher before, as compared with after, therapy. These results indicate that OSAS patients have abnormal ANF secretion. Effective nasal CPAP therapy led to normalization of ANF secretion during sleep. Atrial natriuretic factor, Sleep apnea syndrome This content is only available as a PDF. © 1993 American Sleep Disorders Association and Sleep Research Society