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core body temperature circadian rhythm

Battuvshin Lkhagvasuren, Takakazu Oka
The histaminergic system modulates numerous physiological functions such as wakefulness, circadian rhythm, feeding, and thermoregulation. However, it is not yet known if this system is also involved in psychological stress-induced hyperthermia (PSH) and, if so, which histamine (H) receptor subtype mediates the effect. Therefore, we investigated the effects of pretreatments with intraperitoneal injections of mepyramine (an H1 receptor inverse agonist), cimetidine (an H2 receptor antagonist), and ciproxifan (an H3 receptor inverse agonist) on cage-exchange stress-induced hyperthermia (a model of PSH) by monitoring core body temperature (Tc) during both light (10:00 am-12:00 pm) and dark (10:00 pm-12:00 am) phases in conscious, freely moving rats...
April 2017: Physiological Reports
Shu K E Tam, Sibah Hasan, Harry M C Choi, Laurence A Brown, Aarti Jagannath, Steven Hughes, Mark W Hankins, Russell G Foster, Vladyslav V Vyazovskiy, David M Bannerman, Stuart N Peirson
Circadian rhythms optimize physiology and behavior to the varying demands of the 24 h day. The master circadian clock is located in the suprachiasmatic nuclei (SCN) of the hypothalamus and it regulates circadian oscillators in tissues throughout the body to prevent internal desynchrony. Here, we demonstrate for the first time that, under standard 12 h:12 h light/dark (LD) cycles, object, visuospatial, and olfactory recognition performance in C57BL/6J mice is consistently better at midday relative to midnight...
March 29, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Hisashi Nabenishi, Atusi Yamazaki
This study investigated the correlation between the body surface temperature (BST) and core body temperature of ewes and changes in BST during the prepartum stage in pregnant ewes. Four non-pregnant adult ewes were used in the first experiment. The BST of the upper neck, vaginal temperature (VT), and ambient temperature (AT) were measured every 10 min for seven days and analyzed for correlations. The mean (± SD) BST and VT of ewes during the study period were 35.4 ± 1.7°C and 39.1 ± 0.4°C, respectively, with a correlation of r = 0...
April 21, 2017: Journal of Reproduction and Development
Duttagupta Subhadeep, B N Srikumar, B S Shankaranarayana Rao, Bindu M Kutty
Neurodegeneration of hippocampal structures is implicated in Alzheimer's disease (AD). Patients with AD exhibit 'sundown syndrome' featuring mood swings and anxiety. Although there are studies demonstrating circadian rhythm disruption associated with sundown phenomenon, the mechanisms underlying the emotional disturbances remain elusive. In the present study, we examined the relationship between subiculum (a key hippocampal output structure) and anxiety. Our study demonstrates that bilateral ventral subicular lesion (VSL) leads to anxiogenic behavior...
December 23, 2016: Physiology & Behavior
Jacopo P Mortola
Circadian patterns are at the core of many physiological processes, and their disruption can have short- and long-term consequences. This essay focuses on one of the best known patterns, the daily oscillation of body temperature (Tb), and the possibility of its difference between genders. From human and animal studies globally considered, the tentative conclusion is reached that differences in Tb circadian pattern between genders are very small and probably limited to the timing of the Rhythm, not to its amplitude...
November 17, 2016: Respiratory Physiology & Neurobiology
Stefan Mendt, Martina Anna Maggioni, Michael Nordine, Mathias Steinach, Oliver Opatz, Daniel Belavý, Dieter Felsenberg, Jochim Koch, Peng Shang, Hanns-Christian Gunga, Alexander Stahn
Continuous recordings of core body temperature (CBT) are a well-established approach in describing circadian rhythms. Given the discomfort of invasive CBT measurement techniques, the use of skin temperature recordings has been proposed as a surrogate. More recently, we proposed a heat-flux approach (the so-called Double Sensor) for monitoring CBT. Studies investigating the reliability of the heat-flux approach over a 24-hour period, as well as comparisons with skin temperature recordings, are however lacking...
2017: Chronobiology International
Diane B Boivin, Ari Shechter, Philippe Boudreau, Esmot Ara Begum, Ng Mien Kwong Ng Ying-Kin
This study quantifies sex differences in the diurnal and circadian variation of sleep and waking while controlling for menstrual cycle phase and hormonal contraceptive use. We compared the diurnal and circadian variation of sleep and alertness of 8 women studied during two phases of the menstrual cycle and 3 women studied during their midfollicular phase with that of 15 men. Participants underwent an ultradian sleep-wake cycle (USW) procedure consisting of 36 cycles of 60-min wake episodes alternating with 60-min nap opportunities...
September 27, 2016: Proceedings of the National Academy of Sciences of the United States of America
Christine M Walsh, Leslie Ruoff, Jonathan Varbel, Kathleen Walker, Lea T Grinberg, Adam L Boxer, Joel H Kramer, Bruce L Miller, Thomas C Neylan
OBJECTIVE/BACKGROUND: The brainstem is among the first regions affected in progressive supranuclear palsy (PSP) and is part of the sleep/circadian regulation network. In two small studies, blood pressure and core body temperature circadian patterns were disrupted in PSP; however, it is unclear if circadian activity rhythms are also affected. Our objective was to perform circadian analyses of the rest-activity rhythms in PSP and determine the association with increasing disease severity...
June 2016: Sleep Medicine
Ahmed A Al-Haidary, Khalid A Abdoun, Emad M Samara, Aly B Okab, Mamane Sani, Roberto Refinetti
Camels are well adapted to hot arid environments and can contribute significantly to the economy of developing countries in arid regions of the world. Full understanding of the physiology of camels requires understanding of the internal temporal order of the body, as reflected in daily or circadian rhythms. In the current study, we investigated the daily rhythmicity of 20 physiological variables in camels exposed to natural oscillations of ambient temperature in a desert environment and compared the daily temporal courses of the variables...
August 2016: Research in Veterinary Science
Bun Tsuji, Yasushi Honda, Narihiko Kondo, Takeshi Nishiyasu
We investigated whether heat-induced hyperventilation during exercise is affected by time of day, as diurnal variation leads to higher core temperatures in the evening. Nineteen male subjects were divided into two experiments (protocol 1, n = 10 and protocol 2, n = 9). In protocol 1, subjects performed cycle exercise at 50% peak oxygen uptake in the heat (37°C and 50% RH) in the morning (0600) and evening (1800). Results showed that baseline resting and exercising esophageal temperature (Tes) were significantly (0...
August 1, 2016: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
Gorica Micic, Nicole Lovato, Michael Gradisar, Helen J Burgess, Sally A Ferguson, Leon Lack
Our objectives were to investigate the period lengths (i.e., taus) of the endogenous core body temperature rhythm and melatonin rhythm in delayed sleep-wake phase disorder patients (DSWPD) and non-24-h sleep-wake rhythm disorder patients (N24SWD) compared with normally entrained individuals. Circadian rhythms were measured during an 80-h ultradian modified constant routine consisting of 80 ultrashort 1-h "days" in which participants had 20-min sleep opportunities alternating with 40 min of enforced wakefulness...
August 2016: Journal of Biological Rhythms
Erika Navarrete, Juan Roberto Ortega-Bernal, Lucero Trejo-Muñoz, Georgina Díaz, Rodrigo Montúfar-Chaveznava, Ivette Caldelas
Experimental evidence indicates that during pre-visual stages of development in mammals, circadian regulation is still not under the control of the light-entrainable hypothalamic pacemaker, raising the possibility that the circadian rhythmicity that occurs during postnatal development is under the control of peripheral oscillators, such as the main olfactory bulb (MOB). We evaluated the outcome of olfactory bulbectomy on the temporal pattern of core body temperature and gross locomotor activity in newborn rabbits...
2016: PloS One
Marco Preußner, Florian Heyd
Many aspects of human physiology and behavior display rhythmicity with a period of approximately 24 h. Rhythmic changes are controlled by an endogenous time keeper, the circadian clock, and include sleep-wake cycles, physical and mental performance capability, blood pressure, and body temperature. Consequently, many diseases, such as metabolic, sleep, autoimmune and mental disorders and cancer, are connected to the circadian rhythm. The development of therapies that take circadian biology into account is thus a promising strategy to improve treatments of diverse disorders, ranging from allergic syndromes to cancer...
June 2016: Pflügers Archiv: European Journal of Physiology
Yuki Yasumoto, Chiaki Hashimoto, Reiko Nakao, Haruka Yamazaki, Hanako Hiroyama, Tadashi Nemoto, Saori Yamamoto, Mutsumi Sakurai, Hideaki Oike, Naoyuki Wada, Chikako Yoshida-Noro, Katsutaka Oishi
BACKGROUND: The circadian clock regulates various physiological and behavioral rhythms such as feeding and locomotor activity. Feeding at unusual times of the day (inactive phase) is thought to be associated with obesity and metabolic disorders in experimental animals and in humans. OBJECTIVE: The present study aimed to determine the underlying mechanisms through which time-of-day-dependent feeding influences metabolic homeostasis. METHODS: We compared food consumption, wheel-running activity, core body temperature, hormonal and metabolic variables in blood, lipid accumulation in the liver, circadian expression of clock and metabolic genes in peripheral tissues, and body weight gain between mice fed only during the sleep phase (DF, daytime feeding) and those fed only during the active phase (NF, nighttime feeding)...
May 2016: Metabolism: Clinical and Experimental
S L Christiansen, K Højgaard, O Wiborg, E V Bouzinova
Disturbances of circadian rhythms have been suggested to be a causal factor in the development of major depressive disorder. However, the mechanisms underlying the association between circadian rhythm abnormalities and mood disorders are still unknown. In the current study the association between diurnal pattern of key phase markers (melatonin, corticosterone, and core body temperature) and anhedonic-like behavior was investigated using the highly validated rat chronic mild stress (CMS) model of depression...
September 2016: Neuroscience Research
A Wirz-Justice, K Kräuchi, D P Brunner, P Graw, H J Haug, G Leonhardt, A Sarrafzadeh, J English, J Arendt
Seasonal affective disorder (SAD) is characterised by recurrent episodes in autumn and winter of depression, hypersomnia, augmented appetite with carbohydrate craving, and weight gain, and can be successfully treated with bright light. Circadian rhythm hypotheses (summarized in) have stimulated research into the pathophysiology of SAD, postulating that: 1.The illness is a consequence of delayed phase position, 2.It is correlated with diminished circadian amplitude, or 3.It results from changes in the nocturnal duration between dusk and dawn e...
June 1995: Acta Neuropsychiatrica
Davina Derous, Sharon E Mitchell, Cara L Green, Luonan Chen, Jing-Dong J Han, Yingchun Wang, Daniel E L Promislow, David Lusseau, John R Speakman, Alex Douglas
Food intake and circadian rhythms are regulated by hypothalamic neuropeptides and circulating hormones, which could mediate the anti-ageing effect of calorie restriction (CR). We tested whether these two signaling pathways mediate CR by quantifying hypothalamic transcripts of male C57BL/6 mice exposed to graded levels of CR (10 % to 40 %) for 3 months. We found that the graded CR manipulation resulted in upregulation of core circadian rhythm genes, which correlated negatively with circulating levels of leptin, insulin-like growth factor 1 (IGF-1), insulin, and tumor necrosis factor alpha (TNF-α)...
April 2016: Aging
Ming Huang, Toshiyo Tamura, Zunyi Tang, Wenxi Chen, Shigehiko Kanaya
A wearable thermometry for core body temperature (CBT) measurement has both healthcare and clinical applications. On the basis of the mechanism of bioheat transfer, we earlier designed and improved a wearable thermometry using the dualheat- flux method for CBT measurement. In this study, this thermometry is examined experimentally. We studied a fastchanging CBT measurement (FCCM, 55 min, 12 subjects) inside a thermostatic chamber and performed long-term monitoring of CBT (LTM, 24 h, 6 subjects). When compared with a reference, the CoreTemp CM-210 by Terumo, FCCM shows 0...
February 23, 2016: IEEE Journal of Biomedical and Health Informatics
Soo Young Sim, Kwang Min Joo, Han Byul Kim, Seungjin Jang, Beomoh Kim, Seungbum Hong, Sungwan Kim, Kwang Suk Park
Core body temperature is a reliable marker for circadian rhythm. As characteristics of the circadian body temperature rhythm change during diverse health problems, such as sleep disorder and depression, body temperature monitoring is often used in clinical diagnosis and treatment. However, the use of current thermometers in circadian rhythm monitoring is impractical in daily life. As heart rate is a physiological signal relevant to thermoregulation, we investigated the feasibility of heart rate monitoring in estimating circadian body temperature rhythm...
March 2017: IEEE Journal of Biomedical and Health Informatics
Rong Guo, Steve M Simasko, Heiko T Jansen
BACKGROUND: Circadian rhythms are essential for adapting to the environment. Chronic alcohol consumption often leads to sleep and circadian disruptions, which may impair the life quality of individuals with alcohol use disorders and contribute to the morbidity associated with alcoholism. METHODS: We used a pair-feeding liquid diet alcohol exposure protocol (6 weeks duration) in PER1::LUC transgenic rats to examine the effects of chronic alcohol exposure on: (i) diurnal rhythms of core body temperature and locomotor activity, (ii) plasma corticosterone (CORT) concentrations, and (iii) rhythms of ex vivo Period1 (Per1) expression in the suprachiasmatic nucleus (SCN), pituitary, and adrenal glands...
February 2016: Alcoholism, Clinical and Experimental Research
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