• The Korean Journal of Physiology and Pharmacology
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• 제25권5호
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• pp.449-457
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• 2021

The sleep-wake cycle is regulated by the alternating activity of sleep- and wake-promoting neurons. The dorsal raphe nucleus (DRN) secretes 5-hydroxytryptamine (5-HT, serotonin), promoting wakefulness. Melatonin secreted from the pineal gland also promotes wakefulness in rats. Our laboratory recently demonstrated that daily changes in nitric oxide (NO) production regulates a signaling pathway involving with-no-lysine kinase (WNK), Ste20-related proline alanine rich kinase (SPAK)/oxidative stress response kinase 1 (OSR1), and cation-chloride co-transporters (CCC) in rat DRN serotonergic neurons. This study was designed to investigate the effect of melatonin on NO-regulated WNK-SPAK/OSR1-CCC signaling in wake-inducing DRN neurons to elucidate the mechanism underlying melatonin's wake-promoting actions in rats. Ex vivo treatment of DRN slices with melatonin suppressed neuronal nitric oxide synthase (nNOS) expression and increased WNK4 expression without altering WNK1, 2, or 3. Melatonin increased phosphorylation of OSR1 and the expression of sodium-potassium-chloride co-transporter 1 (NKCC1), while potassium-chloride co-transporter 2 (KCC2) remained unchanged. Melatonin increased the expression of tryptophan hydroxylase 2 (TPH2, serotonin-synthesizing enzyme). The present study suggests that melatonin may promote its wakefulness by modulating NO-regulated WNK-SPAK/OSR1-KNCC1 signaling in rat DRN serotonergic neurons.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.13-18
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• 2014

Sleep is vital to maintain health and well-being; however, insomnia is currently a widespread health complaint worldwide. In particular, caffeine, a psychoactive component of coffee, tea, and caffeine beverages may lead to sleep disorders such as insomnia. In this study, our primary objective was to investigate the inhibitory effect of high-purity phlorotannin preparation (HP-PRT) on caffeine-induced wakefulness. The sleep test of pentobarbital-induced mice was used as an in vivo animal model. Caffeine (50 and 100 mg/kg) showed significant arousal effects (an increase in sleep latency and a decrease in sleep duration). Co-administration of caffeine (50 mg/kg) and the sedative-hypnotic diazepam (DZP, 1 mg/kg) did not result in similar arousal activity. HP-PRT (500 mg/kg) also inhibited caffeine-induced wakefulness. Our results suggest that HP-PRT would be a useful additive for developing coffee products without the arousal effect.

• 수면정신생리
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• 제9권1호
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• pp.14-17
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• 2002

Epilepsy is a paroxysmal disorder caused by abnormal electrical discharges of the brain. As it is characterized by episodic seizures with intervening normal neurological states, some temporal patterns of seizure attacks can be traced. Sleep and wakefulness patterns are one of several factors influencing seizure occurrence. In this article, physiological and pathological influences of sleep on the seizure phenomenon were reviewed. Understanding this relationship between sleep and epilepsy might lead to better understanding of sleep and epilepsy themselves, thus leading to better diagnosis and treatment of each disease.

• 가정과삶의질연구
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• 제32권2호
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• pp.41-52
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• 2014

The present study investigated the sleep patterns 1-to 3-year-old children and examined whether their sleep patterns would predict their early adjustment to daycare centers. The participants were 239 young children attending daycare centers in Seoul. The data on children's sleep patterns were collected by parent report. Children's adjustment to daycare was assessed by daycare providers' reports. The data were analyzed by means of Chi-square test, t-test, Pearson's correlation, ANOVA and discriminant analysis. The results were as follows: Children from dual-earner families had shorter nocturnal sleep duration than those from single-earner families. There was no significant relation between daytime sleep duration and sleep-onset time at night. It was found that children who go to bed earlier were more likely to get sufficient sleep without nocturnal wakefulness. Age and total sleep duration were seen to be significant variables when it came to discriminating between the adjustment versus maladjustment groups.

• 감성과학
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• 제6권4호
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• pp.9-14
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• 2003

수면단계는 수면감을 평가하는 데 있어서 중요한 생리지표로서 사용되어 왔다. 그러나 수면다원검사를 이용한 전통적 수면단계 분류방법은 뇌전도(electroencephalogram : EEG), 안전도(electrooculogram : EOG), 심전도(electrocardiogram : ECG), 근전도(electromyogram : EMG) 등을 종합적으로 측정하므로 수면단계를 비교적 정확히 분류할 수 있지만 피험자에게 심한 구속감을 주는 문제가 있다. 본 연구에서는, 각성상태에서 교감신경계가 지배적인 반면에 수면 중에는 부교감 신경계가 더 활동적인 점에 착안하여 수면단계를 간단히 분류할 수 있는 방법을 찾고자 수면단계에 따른 심박동변이도(heart rate variability : HRY)를 분석하였다. 이 실험에는 건강한 대학생 6명이 2일씩 전체 12회의 야간수면에 참여하였다. 수면다원검사 장치를 이용하여 피험자들이 수면을 취하고 있는 동안, EEG, EOG, ECG, EMG(턱 및 다리)를 측정하여 수면단계를 "Standard scoring system for sleep stage"에 따라 자동으로 분류하였다. 그런 뒤, 본 연구를 통하여 제작된 Sleep Data Acquisition/Analysis 시스템을 이용하여 수면다원검사 장치로부터 ECG신호만 추출하여 HRV의 전력스펙트럼을 3개의 영역[저주파수대역(low frequency : LF), 중간주파수대역(medium frequency : MF), 고주파수대역(high frequency : HF)]으로 나누어 분석하였다. 단일채널 ECG를 이용하여 수면단계별로 HRV의 LF/HF를 분석한 결과, W(wakefulness)단계가 2단계에 비하여 325%높게(p＜.05), 3단계에 비하여 628%높게(p＜.001), 4단계에 비하여 800%높게(p＜.001) 나타났으며, 4단계는 REM(rapid eye movement)단계에 비하여 427% 낮게(p＜.05), 1단계에 비하여 418% 낮게(p＜.05) 나타났다. 또한 LF/HF가 수면단계에 따라 변화하는 양상은 W, REM, 1, 2, 3, 4단계의 순으로 단조 감소하였다. 한편, 수면단계별 MF/(LF+HF)의 차이는 유의하지 않았으나 표본집단의 기술통계치를 살펴본 바 REM단계와 3단계의 평균치가 가장 높았다.치가 가장 높았다.

• Journal of Photoscience
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• 제9권2호
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• pp.406-408
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• 2002

In order to know the characteristics of circadian rhythms in core temperature in tropical inhabitants, we measured rectal temperatures every 10 min for 24 hrs in 6 Vietnamese, 20 - 22 yrs (5 males and I females) under natural conditions. Average light intensity was 16000 lx. Ambient temperatures ranged from 33 to 36 oC. These data obtained were compared with those in Japanese setters and the Polish inhabitants. The participants were sitting mostly during wakefulness and lying in bed during sleep. The results obtained are summarized as follows: I) The average maximum value was 37.7 oC, which was significantly higher than in the Japanese and Polish as well. 2) The average minimum value was 36.4 oC, which was also lower. 3) A range of oscillation was 1.3 oC, which was clearly greater than in the people living in the temperate areas. The higher maximum value of core temperature, which was actively regulated under warm temperature, seemed of adaptive significance in order to reduce water consumption. A greater rage of oscillation in tropical Vietnamese people might have ecological significance for efficient acclimatization in the environment with strong light intensity and high ambient temperature, suggesting that the setpoint of core temperature could show a greater range of oscillation.

• Biomolecules & Therapeutics
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• 제23권3호
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• pp.268-274
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• 2015

${\gamma}$-Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the mammalian central nervous system, is involved in sleep physiology. Caffeine is widely used psychoactive substance known to induce wakefulness and insomnia to its consumers. This study was performed to examine whether GABA extracts from fermented rice germ ameliorates caffeine-induced sleep disturbance in mice, without affecting spontaneous locomotor activity and motor coordination. Indeed, caffeine (10 mg/kg, i.p.) delayed sleep onset and reduced sleep duration of mice. Conversely, rice germ ferment extracts-GABA treatment (10, 30, or 100 mg/kg, p.o.), especially at 100 mg/kg, normalized the sleep disturbance induced by caffeine. In locomotor tests, rice germ ferment extracts-GABA slightly but not significantly reduced the caffeine-induced increase in locomotor activity without affecting motor coordination. Additionally, rice germ ferment extracts-GABA per se did not affect the spontaneous locomotor activity and motor coordination of mice. In conclusion, rice germ ferment extracts-GABA supplementation can counter the sleep disturbance induced by caffeine, without affecting the general locomotor activities of mice.

• 한국전자통신학회논문지
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• 제8권6호
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• pp.949-954
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• 2013

본 논문에서는 인간의 졸음에 대한 특성을 관찰하기 위해 뇌파를 계측 및 분석하였다. 인간으로부터 발생되는 뇌파 즉 EEG신호를 계측하여 주파수 대역에 따라 분석하는 것을 기본적인 방법으로 한다. 흔히 각성, 폐안 및 수면에 접어들 때와 관련이 있는 뇌파는 알파파로 알려져 있다. 따라서 본 논문에서는 졸음과 관련된 분석 주파수대역을 알파파대역으로 한정하여, 알파파대역 중에서도 어떤 주파수성분이 졸음과 더 밀접한 관련이 있는지 파워 스펙트럼 분석법을 이용하여 관측한 결과를 제시하였다.

• 수면정신생리
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• 제3권2호
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• pp.43-55
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• 1996

Since REM sleep was found to be closely related with dream, efforts have been made to find the neurophysiological mechanism and the psychological meaning of dream. However, since most researchers have paid attention to dreams of adults, there are relatively few studies devoted to those of developing children. In the prevent study, we reviewed the previous studies and hypotheses about sleep and dream in various aspects and summarized the characteristics of sleep and dream of children in developmental domain as followings. (1) Sleep development : Across childhood, sleep architecture and sleep-wakefulness cycles are progressively changed toward the patterns of adult. They become similar to adult patterns only in their adolescence. Thus, the sleep event sconsidered as abnormal in adults may be normal in children. (2) Dream development : First, the content and meaning of the dream change with increasing age and develop in parallel with children's ego function, especially cognitive developmental stages. Second, for the children, the reality and the dream are on the continuous spectrum of 'reality-imitation-play-fantasy-dream'. Third, dreaming is the pure assimilation process for the children and through dreaming they can adapt and accomodate the reality without emotion.

• Natural Product Sciences
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• 제23권1호
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• pp.53-60
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• 2017

Perillae Herba has been traditionally used for the sedation in the oriental countries. Therefore, this study was conducted to determine whether Perillae Herba ethanol extract (PHEE) enhances pentobarbital-induced sleeping behaviors in animals. In addition, the possible mechanisms are demonstrated. PHEE (12.5, 25 and 50 mg/kg. p.o.) reduced the locomotor activity in mice. PHEE reduced sleep latency and augmented the total sleep time in pentobarbital (42 mg/kg, i.p.)-induced sleep in mice. Furthermore, the number of sleeping mice treated with sub-hypnotic pentobarbital (28 mg/kg, i.p.) increased. PHEE (50 mg/kg. p.o.) decreased the sleep/wake cycles and wakefulness, and increased total sleeping time and NREM sleep in electroencephalogram (EEG) of rats. In addition, PHEE (0.1, 1.0 and $10{\mu}g/ml$) increased the intracellular $Cl^-$ level through the GABA receptors in the hypothalamus of rats. Moreover, the protein of glutamate decarboxylase (GAD) was overexpressed by PFEE. It was found that PHEE enhanced pentobarbital-induced sleeping behaviors through $GABA_A-ergic$ transmissions.