Dissociation of circadian rhythms in rats with a hypothalamic island

1984 ◽  
Vol 246 (6) ◽  
pp. R949-R954
Author(s):  
S. Honma ◽  
K. Honma ◽  
T. Hiroshige
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Locomotor Activity ◽  
Corticosterone Level ◽  
Direct Consequence ◽  
Plasma Corticosterone ◽  
Spontaneous Locomotor Activity ◽  
Medial Basal Hypothalamus ◽  
The Central Nervous System

Complete isolation of the medial basal hypothalamus, including the suprachiasmatic nuclei in the isolated island, from the rest of the central nervous system was performed in rats. The circadian rhythm of plasma corticosterone level remained essentially intact in 5 of 16 rats with complete islands, whereas that of spontaneous locomotor activity was decomposed into ultradian bursts in 15 rats, resulting in a clear dissociation of the two rhythms in four rats. One rat, whose circadian rhythm of both variables persisted after the hypothalamic isolation, showed a diurnal activity. The 24-h patterns of plasma corticosterone of the other rats could be characterized as either episodic or continuously low throughout the day. A prefeeding corticosterone peak was detected under restricted feeding in rats with episodic fluctuations but not in those with continuously low hormone levels. It is concluded that the hypothalamic island includes the fundamental structures necessary for the manifestation of the entrained circadian rhythm of plasma corticosterone in rats under ad libitum feeding, whereas it contains only a part of that for spontaneous locomotor activity. The coupling pathways from the circadian oscillator(s) to these overt rhythms seem to be separate in the central nervous system, and the circadian rhythm of plasma corticosterone is not a direct consequence of that of locomotor activity.

Photic sensitivity of the rhinophore in Aplysia

1979 ◽  
Vol 57 (3) ◽  
pp. 698-701 ◽  
Author(s):  
Ronald Chase
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Locomotor Activity ◽  
Peripheral Nerve ◽  
Aplysia Californica ◽  
Optic Nerves ◽  
Peripheral Location ◽  
The Central Nervous System

A response to the onset of light was recorded electrophysiologically from the rhinophore nerve of Aplysia californica. Except for the optic nerves, no other peripheral nerve is known to carry photic information to the central nervous system. The result suggests a peripheral location for the extraocular photoreceptors which are known to be capable of controlling the circadian rhythm of locomotor activity.

The effect of Qing Huan Ling combined risperidone on the open field behavior of schizophrenic mice model

2016 ◽  
Vol 33 (S1) ◽  
pp. s289-s289
Author(s):  
Y. Zhang ◽  
F. Liu ◽  
Z. Dai ◽  
B. Wu ◽  
Q. Wu
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Locomotor Activity ◽  
Open Field ◽  
Open Field Test ◽  
Model Group ◽  
Mice Model ◽  
Blank Group ◽  
The Central Nervous System ◽  
Risperidone Group

ObjectiveTo observe the effect of Qing Huan Ling and (or) risperidone on locomotor activity and explorative behavior of schizophrenia mice model by open field test.MethodsSeventy kunming mice were randomly divided into 5 groups, one group as blank group. The rest groups ip MK-801 continuously 14 day, then randomly numbered: model group, risperidone group, Qing Huan Ling group and risperidone combined Qing Huan Ling group. Ig give corresponding drugs for each group 4 weeks, observe the change of locomotor activity and explorative behavior by open field test.ResultsAfter Ig 4 weeks, compared with the blank group, there were no obvious difference in locomotor activity and explorative behavior between risperidone group, Qing Huan Ling group and the combined group. Compared with the model group, risperidone had statistics meaning in the repression of explorative behavior (P < 0.05),the combined group has statistics meaning in the repression of locomotor activity and explorative behavior (78.92 ± 36.18 m vs. 186.92 ± 41.08 m, P < 0.01).ConclusionQing Huan Ling regulate the central nervous system of schizophrenia mice model; when combined with risperidone, it restrain the central nervous system of schizophrenia mice model and the effect is stronger than risperidone alone.Disclosure of interestThe authors have not supplied their declaration of competing interest.

THE INFLUENCE OF DIPHENYLHYDANTOIN AND CARBAMAZEPINE ON THE CIRCADIAN RHYTHM OF FREE URINARY CORTICOIDS AND ON THE SUPPRESSIBILITY OF THE BASAL AND THE "IMPULSIVE" ACTIVITY BY DEXAMETHASONE

1973 ◽  
Vol 72 (2) ◽  
pp. 308-318 ◽  
Author(s):  
J. Köbberling ◽  
A. v. zur Mühlen
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Feedback Mechanism ◽  
Essential Condition ◽  
The Central Nervous System ◽  
Competitive Protein Binding ◽  
Pre Treatment ◽  
Higher Doses

ABSTRACT In eight normal volunteers the circadian rhythm of cortisol was established by the determination of free urinary corticoids in 2 h urine samples by the competitive protein binding method. After two control days dexamethasone was infused between 10 p. m. and 4 a. m. in doses between 50 and 400 μg/h. These experiments were repeated after pre-treatment with 400 mg diphenylhydantion/day for one week and again after pre-treatment with 800 mg carbamazepine/day. Under the influence of these anti-convulsant drugs the circadian rhythm of free urinary corticoids was still present but showed more irregularities and sometimes additional peaks in the course of the day. The 24 h excretion values, the peak and the nadir values and the time of the morning peaks were not significantly different from the control days. The degree of suppression by dexamethasone was dose related both with and without the application of the anti-convulsants but under the influence of both these drugs comparable effects could only be achieved by 2 to 4 fold higher doses of dexamethasone. The suppression of basal and impulsive cortisol activities was inhibited in a similar way. According to these results it can be assumed that the anti-convulsants interfere with the feedback mechanism by decreasing the sensitivity of the central nervous system to changes in plasma glucocorticoid concentrations. An intact feedback mechanism does not seem to be an essential condition for the circadian rhythm.

Regional physiological adaptation of the central nervous system deiodinases to iodine deficiency

2001 ◽  
Vol 281 (1) ◽  
pp. E54-E61 ◽  
Author(s):  
Robin Peeters ◽  
Csaba Fekete ◽  
Carla Goncalves ◽  
Gabor Legradi ◽  
Helen M. Tu ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Pituitary Gland ◽  
Iodine Deficiency ◽  
Fold Increase ◽  
Physiological Adaptation ◽  
Medial Basal Hypothalamus ◽  
Iodothyronine Deiodinases ◽  
The Central Nervous System

The goal of the present investigation was to analyze the types 2 (D2) and 3 (D3) iodothyronine deiodinases in various structures within the central nervous system (CNS) in response to iodine deficiency. After 5–6 wk of low-iodine diet (LID) or LID + 2 μg potassium iodide/ml (LID+KI; control), rats' brains were processed for in situ hybridization histochemistry for D2 and D3 mRNA or dissected, frozen in liquid nitrogen, and processed for D2 and D3 activities. LID did not affect weight gain or serum triiodothyronine, but plasma thyroxine (T4) was undetectable. In the LID+KI animals, D3 activities were highest in the cerebral cortex (CO) and hippocampus (HI), followed by the olfactory bulb and was lowest in cerebellum (CE). Iodine deficiency decreased D3 mRNA expression in all CNS regions, and these changes were accompanied by three- to eightfold decreases in D3 activity. In control animals, D2 activity in the medial basal hypothalamus (MBH) was similar to that in pituitary gland. Of the CNS D2-expressing regions analyzed, the two most responsive to iodine deficiency were the CO and HI, in which an ∼20-fold increase in D2 activity occurred. Other regions, i.e., CE, lateral hypothalamus, MBH, and pituitary gland, showed smaller increases. The distribution of and changes in D2 mRNA were similar to those of D2 activity. Our results indicate that decreases in the expression of D3 and increases in D2 are an integral peripheral component of the physiological response of the CNS to iodine deficiency.

scholarly journals Anxiolytic-like effect of natural product 2-hydroxy-3,4,6-trimethoxyacetophenone isolated from Croton anisodontus in adult zebrafish via serotonergic neuromodulation involvement of the 5-HT system

2021 ◽  
Author(s):  
Antonio Wlisses da Silva ◽  
Maria Kueirislene A. Ferreira ◽  
Emanuela L. Rebouças ◽  
Francisco Rogenio S. Mendes ◽  
Atilano Lucas dos S. Moura ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Locomotor Activity ◽  
Acute Toxicity ◽  
Natural Product ◽  
Anxiolytic Effect ◽  
Mechanisms Of Action ◽  
Anticonvulsant Effect ◽  
Adult Zebrafish ◽  
The Central Nervous System

Abstract Benzodiazepines are highly effective in combating anxiety; however, they have considerable adverse effects, so it is important to discover new safe anxiolytic agents. This study was designed to investigate the anxiolytic and anticonvulsant effect of natural product 2-hydroxy-3,4,6-trimethoxyacetophenone (HTMCX) and its possible mechanisms of action in adult zebrafish. The open field and light / dark tests (n = 6 animals/group) were used to assess anxiety and pentylenetetrazole (PTZ) as a seizure inducer. The 96-hour acute toxicity of HTMCX was also investigated. HTMCX (1, 3, and 10 mg / kg; v.o.) was not toxic and affected locomotor activity. The highest doses (3 and 10 mg / kg; v.o.) produced signs of anxiolytic action in the light / dark test, and this effect was abolished by the pizotifen (antagonist 5HTR1 and 5HTR2A / 2C), having the potential to form a complex in the same region of the site indicating that the anxiolytic effect via the serotonergic mechanism. However, the anxiolytic effect of HTMCX has not been abolished by flumazenil (antagonist GABARA), cyproheptadine (antagonist 5HTR2A), and granisetron (antagonist 5HTR3A / 3B). Therefore, HTMCX demonstrated an anxiolytic effect, suggesting that the 5HTR1 and 5HTR / 2C receptors may be involved in the pharmacological performance of this acetophenone in the central nervous system.

Circadian Rhythm Sleep Disorders as a Possible Side Effect of Fluvoxamine

CNS Spectrums ◽  
2001 ◽  
Vol 6 (6) ◽  
pp. 511-513 ◽  
Author(s):  
Haggai Hermesh ◽  
Hadas Lemberg ◽  
Judith Abadi ◽  
Yaron Dagan
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Sleep Disorders ◽  
Psychotropic Drugs ◽  
Side Effect ◽  
Sleep Problems ◽  
Sleeping Pills ◽  
Circadian Rhythm Sleep Disorders ◽  
The Central Nervous System

AbstractSleep problems, day somnolence, and fatigue as a result of psychotropic drugs are very common. Psychiatrists usually consider these effects a result of insomnia and treat them by prescribing sleeping pills or other benzodiazepine agents.We describe here 10 cases of circadian rhythm sleep disorders (CRSD)—and not merely insomnia—as a possible side effect of fluvoxamine (FVA). Two other serotonin reuptake inhibitors, fluoxetine and clomipramine, did not induce CRSD in any of these 10 patients. We speculate that FVA-induced CRSD is caused by the effect of FVA on serotonin and melatonin levels in the central nervous system.CRSD as a side effect of FVA can be treated by replacing the suspected FVA or adding melatonin to a beneficial FVA treatment. Thus, it is important to be aware of possible iatrogenic CRSD in order to treat appropriately. Prospective studies are needed to confirm our observation and to study the influence of other psychotropic drugs on sleep-wake schedule.

Postnatal Development of Circadian Rhythm in Serum Cortisol Levels in Children

PEDIATRICS ◽  
1983 ◽  
Vol 72 (3) ◽  
pp. 399-404 ◽  
Author(s):  
Shoju Onishi ◽  
Genji Miyazawa ◽  
Yutaka Nishimura ◽  
Satoru Sugiyama ◽  
Takeshi Yamakawa ◽  
...  
Keyword(s):  
Central Nervous System ◽  
High Pressure ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Liquid Chromatography ◽  
Congenital Anomalies ◽  
Serum Cortisol ◽  
Endocrine Diseases ◽  
The Central Nervous System

High-pressure liquid chromatography was used to study the development of blood adrenocortical circadian rhythm in a total of 64 children, ranging in age from 1 month to 15 years. Patients with endocrine diseases, congenital anomalies, and diseases of the central nervous system were excluded from this study. Determination of corticosteroid concentration was possible with 20 to 100 µL of serum. Twenty-four hour patterns were determined at six-hour intervals. A distinct circadian rhythm with an amplitude comparable to that of an adult emerged at approximately 6 months of age.

Sign in / Sign up

Export Citation Format

Share Document