Authorship：Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Brain monoaminergic neurotransmitters, such as dopamine (DA), serotonin (5-HT), and noradrenaline (NA), play crucial roles in neuronal and physiological functions, including social behaviors. Isolation housing may induce behavioral and neurochemical abnormalities in rats, although its influence on neurotransmitter levels remains obscure. This study investigated the influence of isolation- or group-housing on core body temperature (Tcore ), locomotor activity (ACT), emotional behavior, and neurotransmitter levels in male Wistar rats. Behavioral changes were monitored using the open field test (OFT) and social interaction test (SIT). After 4 weeks, brain tissues were collected to quantify 5-HT, DA, and NA concentrations. Body weight and basal Tcore during both the light and dark phase were higher in isolation-housed than in group-housed rats, although no significant difference was seen in ACT. No significant differences were observed during the OFT. Isolation-housed rats showed increased line crossing and decreased social behavior during the SIT. Isolation-housed rats exhibited decreased levels of 5-HT in the caudate putamen and amygdala, and elevated and decreased NA levels in the paraventricular hypothalamic nucleus and hippocampus, respectively. However, DA levels were unaffected. Thus, housing environments may affect brain areas that regulate various neuronal and physiological functions, such as memory, stress responses, and emotional behavior.

DOI： 10.1002/dev.22036

PubMed

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：(一社)日本体力医学会  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

Brain monoamines-such as noradrenaline (NA), dopamine (DA) and serotonin (5-HT)-regulate several important physiological functions, including the circadian rhythm. The purpose of this study was to examine changes in NA, DA and 5-HT levels in various brain regions and their effect on core body temperature (T-c), heart rate (HR) and locomotor activity (Act) in rats following exposure to an artificial light/dark (LD) cycle. For this, male Wistar rats were housed at an ambient temperature (T-a) of 23 degrees C and 50% relative humidity with free access to food and water. Rats were exposed to either natural (12 h: 12 h) or artificial (6 h: 6 h) LD cycles for 1 month, after which each brain region was immediately extracted and homogenized to quantify the amounts of NA, DA and 5-HT by high-performance liquid chromatography. Behavioural changes were also monitored by the ambulatory activity test (AAT). Notably, we found that artificial LD cycles disrupted the physiological circadian rhythms of T-c, HR and Act. Although the 5-HT levels of rats with a disrupted circadian rhythm decreased in cell bodies (dorsal and median raphe nuclei) and projection areas (frontal cortex, caudate putamen, preoptic area and suprachiasmatic nucleus) relative to the control group, NA levels increased both in the cell body (locus coeruleus) and projection area (paraventricular hypothalamus). No significant changes were found with respect to DA. Moreover, circadian rhythm-disrupted rats also showed anxious behaviours in AAT. Collectively, the results of this study suggest that the serotonergic and noradrenergic systems, but not the dopaminergic system, are affected by artificial LD cycles in brain regions that control several neural and physiological functions, including the regulation of physiological circadian rhythms, stress responses and behaviour.

DOI： 10.3109/07420528.2015.1105250

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (scientific journal)  

J-GLOBAL

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)   Publisher：Rikkyo University  

CiNii Article

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Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

The purpose of the present study was to investigate the relationship between thermoregulation and catecholamine release in the preoptic area and anterior hypothalamus (PO/AH) during incremental treadmill running in the rat. To this aim, we combined in vivo brain microdialysis, biotelemetry and metabolic measurements for continuous monitoring of core body temperature (T-core), neurotransmitters and thermoregulatory responses. The animals were exercised for 1 h at 23 degrees C. Treadmill speed was increased every 20 min (10, 20 and 26 m min(-1)). T-core. oxygen consumption (VO2, an index of heat production) and tail skin temperature (T-tail, an index of heat loss) were simultaneously measured. Brain microdialysis samples were collected every 10 min, and these samples were analyzed for noradrenaline (NA), dopamine (DA) and serotonin (5-HT). T-core and VO2 significantly increased during treadmill and were exercise intensity dependent. After an initial drop T-tail increased significantly during exercise. Both NA and DA levels in the PO/AH increased significantly during exercise. There was no effect on serotonin release. T-core. VO2 and T-tail were positively correlated with the levels of NA and DA. Our data suggest that thermoregulatory responses are dependent on the intensity of the exercise and that these responses are associated with changes in NA and DA release, but not in 5-HT release in the PO/AH. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jneumeth.2011.05.024

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Language：Japanese   Publishing type：Research paper (scientific journal)  

CiNii Article

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

The aim of the present study was to assess the response of serotonin (5-hydroxytryptamine; 5-HT) in the preoptic area and anterior hypothalamus (PO/AH) to thermoregulation during exercise in a warm environment. In addition, it was investigated whether a rapid increase in extracellular 5-HT levels in the PO/AH modifies the thermoregulatory response under the same exercise conditions. Rats were made to run for 120 min at 10 m min(-1) on a treadmill at the ambient temperature of 30 degrees C. Body core temperature (T-core) was monitored using a biotelemetry system, and tail skin temperature (T-tail) was simultaneously measured as an index of heat loss response. Microdialysis in combination with HPLC was used to measure concentrations of monoamines in the PO/AH. Both T-core and T-tail increased during the first 20 min of exercise and remained stable until the end of the exercise period. Low-intensity exercise did not induce any changes in 5-HT release in the PO/AH, although the levels of norepinephrine and dopamine were increased. Moreover, increased extracellular 5-HT by local perfusion of 1 mu M citalopram (selective 5-HT reuptake inhibitor; SSRI) in the PO/AH had no effect on the thermoregulatory response during acute low-intensity exercise in a warm environment. These results suggest that enhanced release of only 5-HT in the PO/AH may not intervene thermoregulation during exercise in a warm environment. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2010.06.073

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

For this study, we compared the thermoregulatory involvement of noradrenaline (NA) in the medial preoptic area (mPOA) of non-cold acclimated rats to that of cold-acclimated rats. We quantified the release of NA in the mPOA during 3 h cold (5 degrees C) exposure in room-temperature-acclimated rats (RA group, kept at 23 degrees C for 2 weeks) and cold-acclimated rats (CA group, kept at 5 degrees C for 2 weeks). We concurrently monitored the core body temperature (T-c), heart rate (HR), and tail skin temperature (T-t). Cold exposure significantly increased T-c and HR, and decreased Tt in both groups. However, the cold-induced increase of the extracellular NA levels in mPOA was observed only in the RA group: not in the CA group. To elucidate these different results in NA levels further, and to evaluate participation of the mPOA in thermoregulation in the cold, we measured T-c, HR, and T-t during perfusion of alpha-adrenoceptor antagonist phenoxybenzamine during cold exposure (5 degrees C). This pharmacological procedure induced marked hypothermia, with decreases in HR only in the RA group; no changes were observed in T-c or any thermoregulatory parameter in the CA group. These results suggest that NA in the mPOA modulates heat production in response to acute cold stress in the RA group. However, this thermoregulatory action of NA in the mPOA was attenuated in the CA group. (C) 2008 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.lfs.2008.05.008

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Language：English   Publishing type：Research paper (scientific journal)  

CiNii Article

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Academy of Sleep Medicine  

Study Objectives: We hypothesized that appropriate changes in thermal environment would enhance the quality of sleep. Design/Setting: Controlled laboratory study. Participants: Healthy young men (n = 7, mean age 26 years). Interventions: Nocturnal sleep structures in semi-nude subjects were compared between a condition where an ambient temperature (Ta) of 29.5°C was maintained throughout the night (constant Ta), and a second condition (dynamic Ta) where Ta changed slowly within the thermoneutral range (from 27.5°C to 29.5°C). Measurements and Results: Statistically significant (P &lt
0.05) results included a lower and a later occurrence of minimum core body temperature (Tc), and a longer duration of slow-wave (stages 3+4) sleep in dynamic versus constant T a. However, total sleep time, sleep efficiency, the total durations of light (stages 1+2) and rapid eye movement sleep, and the latencies to sleep onset, slow-wave sleep, and rapid eye movement sleep did not differ between conditions. Conclusions: Lowering the minimum and delaying the nadir of nocturnal Tc increases slow-wave sleep (probably by an increase of dry heat loss)
use of this tactic might improve the overall quality of sleep.

DOI： 10.1093/sleep/30.6.797

Scopus

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS INC  

Study Objectives: We hypothesized that appropriate changes in thermal environment would enhance the quality of sleep.
Design/Setting: Controlled laboratory study.
Participants: Healthy young men (n = 7, mean age 26 years).
Interventions: Nocturnal sleep structures in semi-nude subjects were compared between a condition where an ambient temperature (T-a) of 29.5 degrees C was maintained throughout the night (constant T-a), and a second condition (dynamic T-a) where T-a changed slowly within the thermoneutral range (from 27.5 degrees C to 29.5 degrees C).
Measurements and Results: Statistically significant (P < 0.05) results included a lower and a later occurrence of minimum core body temperature (T.), and a longer duration of slow-wave (stages 3+4) sleep in dynamic versus constant T-a. However, total sleep time, sleep efficiency, the total durations of light (stages 1+2) and rapid eye movement sleep, and the latencies to sleep onset, slow-wave sleep, and rapid eye movement sleep did not differ between conditions.
Conclusions: Lowering the minimum and delaying the nadir of nocturnal T c increases slow-wave sleep (probably by an increase of dry heat loss); use of this tactic might improve the overall quality of sleep.

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publishing type：Research paper (other academic)   Publisher：杏林書院  

CiNii Article

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Other Link： http://search.jamas.or.jp/link/ui/2005149806

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日本児童学会  

CiNii Article

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Language：English   Publishing type：Research paper (scientific journal)  

CiNii Article

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Language：Japanese   Publishing type：Research paper (other academic)   Publisher：杏林書院  

CiNii Article

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Other Link： http://search.jamas.or.jp/link/ui/2005126282

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier Ltd  

Action of norepinephrine (NE), serotonin (5-HT) and dopamine (DA) in the hypothalamus have been reported to play key roles in several homeostatic functions, including thermoregulation. The purpose of this study was to clarify differences in concentrations of NE, 5-HT and DA in several hypothalamic regions after cold exposure of different durations. Rats were exposed to a cold environment (5°C) for 3 hours (3H), 1 day (1D), 7 days (7D), 14 days (14D), or 28 days (28D). After cold exposure, each hypothalamic region was immediately extracted and homogenized. NE, 5-HT and DA in the extract were measured by high-performance liquid chromatography. We observed marked differences in the concentration of NE in each hypothalamic region after cold exposures. NE in the preoptic area was high only in the 3H group, while it was elevated in the 7D, 14D and 28D groups in the ventromedial hypothalamus. On the other hand, NE in the posterior hypothalamus was low in the 3H, 1D, 7D and 14D groups. Cold exposure did not affect concentrations of 5-HT and DA in these hypothalamic regions. Our results suggest the involvement of NE in each hypothalamic region in maintenance of body temperature, and that the neuronally active site in the hypothalamus seems to change during cold acclimation. © 2005 Published by Elsevier Ltd.

DOI： 10.1016/j.jtherbio.2004.12.001

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Language：English   Publishing type：Research paper (scientific journal)  

CiNii Article

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Language：English   Publishing type：Doctoral thesis  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI IRELAND LTD  

To clarify the role of the preoptic area and anterior hypothalamus (PO/AH) on thermoregulatory system and the effects of serotonergic innervation from the median raphe nucleus (MRN) on body temperature (Tb), we perfused tetrodotoxin (TTX) solution into the PO/AH or MRN by using a microdialysis technique at different ambient temperatures (5, 23 and 35 degreesC) in freely moving rats. Tb was continuously monitored by using a telemetry system. In the MRN, perfusion of TTX solution induced significant hypothermia in the normal environment, a greater decrease in Tb during cold exposure and had no effect on Tb during heat exposure. In the PO/AH, perfusion of TTX solution induced Significant hyperthermia in normal environment, a greater increase in Tb during heat exposure and had no effect on Tb during cold exposure. Our results indicate that the PO/AH regulates mainly heat loss or inhibits the loci regulating heat production. Furthermore, heat production appears to be regulated by other loci receiving serotonergic innervation from the MRN. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

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Language：Japanese   Publishing type：Master’s thesis  

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Language：Japanese  

J-GLOBAL

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Language：Japanese Book type：Scholarly book

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Language：Japanese Book type：Other

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