Phase advances of circadian rhythms in somatostatin depleted rats: effects of cysteamine on rhythms of locomotor activity and electrical discharge of the suprachiasmatic nucleus

1994 ◽  
Vol 175 (6) ◽  
Author(s):  
C. Fukuhara ◽  
S.-I.T. Inouye ◽  
K. Aoki ◽  
T. Hamada ◽  
S. Shibata ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Suprachiasmatic Nucleus ◽  
Electrical Discharge

scholarly journals Drugs of Abuse Can Entrain Circadian Rhythms

2007 ◽  
Vol 7 ◽  
pp. 203-212 ◽  
Author(s):  
Ann E. K. Kosobud ◽  
Andrea G. Gillman ◽  
Joseph K. Leffel ◽  
Norman C. Pecoraro ◽  
G. V. Rebec ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Drug Metabolism ◽  
Suprachiasmatic Nucleus ◽  
Drugs Of Abuse ◽  
Social Cues ◽  
Dark Cycle ◽  
Drug Reward ◽  
Locomotor Stimulation ◽  
Almost All

Circadian rhythms prepare organisms for predictable events during the Earth's 24-h day. These rhythms are entrained by a variety of stimuli. Light is the most ubiquitous and best known zeitgeber, but a number of others have been identified, including food, social cues, locomotor activity, and, most recently drugs of abuse. Given the diversity of zeitgebers, it is probably not surprising that genes capable of clock functions are located throughout almost all organs and tissues. Recent evidence suggests that drugs of abuse can directly entrain some circadian rhythms. We have report here that entrainment by drugs of abuse is independent of the suprachiasmatic nucleus and the light/dark cycle, is not dependent on direct locomotor stimulation, and is shared by a variety of classes of drugs of abuse. We suggest that drug-entrained rhythms reflect variations in underlying neurophysiological states. This could be the basis for known daily variations in drug metabolism, tolerance, and sensitivity to drug reward. These rhythms could also take the form of daily periods of increased motivation to seek and take drugs, and thus contribute to abuse, addiction and relapse.

scholarly journals IA Channels Encoded by Kv1.4 and Kv4.2 Regulate Neuronal Firing in the Suprachiasmatic Nucleus and Circadian Rhythms in Locomotor Activity

2012 ◽  
Vol 32 (29) ◽  
pp. 10045-10052 ◽  
Author(s):  
D. Granados-Fuentes ◽  
A. J. Norris ◽  
Y. Carrasquillo ◽  
J. M. Nerbonne ◽  
E. D. Herzog
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Suprachiasmatic Nucleus ◽  
Neuronal Firing

Identification of the suprachiasmatic nucleus in birds

2001 ◽  
Vol 280 (4) ◽  
pp. R1185-R1189 ◽  
Author(s):  
Takashi Yoshimura ◽  
Shinobu Yasuo ◽  
Yoshikazu Suzuki ◽  
Eri Makino ◽  
Yuki Yokota ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Circadian Clock ◽  
Suprachiasmatic Nucleus ◽  
Japanese Quail ◽  
Clock Genes ◽  
Biological Clock ◽  
Circadian Oscillators ◽  
Circadian Clock Genes ◽  
Dim Light

Circadian rhythms are generated by an internal biological clock. The suprachiasmatic nucleus (SCN) in the hypothalamus is known to be the dominant biological clock regulating circadian rhythms in mammals. In birds, two nuclei, the so-called medial SCN (mSCN) and the visual SCN (vSCN), have both been proposed to be the avian SCN. However, it remains an unsettled question which nuclei are homologous to the mammalian SCN. We have identified circadian clock genes in Japanese quail and demonstrated that these genes are expressed in known circadian oscillators, the pineal and the retina. Here, we report that these clock genes are expressed in the mSCN but not in the vSCN in Japanese quail, Java sparrow, chicken, and pigeon. In addition, mSCN lesions eliminated or disorganized circadian rhythms of locomotor activity under constant dim light, but did not eliminate entrainment under light-dark (LD) cycles in pigeon. However, the lesioned birds became completely arrhythmic even under LD after the pineal and the eye were removed. These results indicate that the mSCN is a circadian oscillator in birds.

scholarly journals Assaying Locomotor Activity to Study Circadian Rhythms and Sleep Parameters in Drosophila

10.3791/2157 ◽  
2010 ◽  
Author(s):  
Joanna C. Chiu ◽  
Kwang Huei Low ◽  
Douglas H. Pike ◽  
Evrim Yildirim ◽  
Isaac Edery
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Sleep Parameters

Effects of volatile anesthetics on the circadian rhythms of rat hippocampal acetylcholine release and locomotor activity

Neuroscience ◽  
2013 ◽  
Vol 237 ◽  
pp. 151-160 ◽  
Author(s):  
T. Kikuchi ◽  
H. Tan ◽  
T. Mihara ◽  
K. Uchimoto ◽  
D. Mitsushima ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Circadian Rhythms ◽  
Acetylcholine Release ◽  
Volatile Anesthetics

Light-induced suppression of the rat circadian system

1995 ◽  
Vol 268 (5) ◽  
pp. R1111-R1116 ◽  
Author(s):  
P. Depres-Brummer ◽  
F. Levi ◽  
G. Metzger ◽  
Y. Touitou
Keyword(s):  
Locomotor Activity ◽  
Body Temperature ◽  
Circadian Rhythms ◽  
Prolonged Exposure ◽  
Light Exposure ◽  
Continuous Light ◽  
Circadian System ◽  
Short Exposure ◽  
Complete Suppression ◽  
Continuous Darkness

In a constant environment, circadian rhythms persist with slightly altered period lengths. Results of studies with continuous light exposure are less clear, because of short exposure durations and single-variable monitoring. This study sought to characterize properties of the oscillator(s) controlling the rat's circadian system by monitoring both body temperature and locomotor activity. We observed that prolonged exposure of male Sprague-Dawley rats to continuous light (LL) systematically induced complete suppression of body temperature and locomotor activity circadian rhythms and their replacement by ultradian rhythms. This was preceded by a transient loss of coupling between both functions. Continuous darkness (DD) restored circadian synchronization of temperature and activity circadian rhythms within 1 wk. The absence of circadian rhythms in LL coincided with a mean sixfold decrease in plasma melatonin and a marked dampening but no abolition of its circadian rhythmicity. Restoration of temperature and activity circadian rhythms in DD was associated with normalization of melatonin rhythm. These results demonstrated a transient internal desynchronization of two simultaneously monitored functions in the rat and suggested the existence of two or more circadian oscillators. Such a hypothesis was further strengthened by the observation of a circadian rhythm in melatonin, despite complete suppression of body temperature and locomotor activity rhythms. This rat model should be useful for investigating the physiology of the circadian timing system as well as to identify agents and schedules having specific pharmacological actions on this system.

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