Exogenous and Endogenous Control of Swimming Activity in Astyanax mexicanus (Characidae, Pisces) by Direct Light Response and by a Circadian Oscillator I. Analyses of the Time-Control Systems of an Epigean River Population

1982 ◽  
Vol 37 (11-12) ◽  
pp. 1253-1265 ◽  
Author(s):  
Wilhelmine Erckens ◽  
Wolfgang Martin
Keyword(s):  
Circadian Rhythm ◽  
Surface Activity ◽  
Phase Relation ◽  
Total Activity ◽  
Swimming Activity ◽  
Circadian Oscillator ◽  
Constant Darkness ◽  
River Population ◽  
Astyanax Mexicanus ◽  
Time Control

Abstract 1. The swimming activity of 6 specimens of an Astyanax mexicanus' river population was tested with regard to its time control under various light-dark(LD)cycles and under constant conditions. 2. Activity is classified into three different forms according to the special experimental arrangement: surface activity, bottom activity and the sum of both (total activity). 3. All applied LD-cycles act as socalled forcing signals (Zeitgeber) and entrain the activity. 4. The maximum values of surface activity correspond to the dark phases of a LD-cycle, those of bottom activity to the light phases. This inversity causes a less strong entrainment of the total activity up to a loss of a significant oscillation in extreme cases. 5. This inverse pattern is kept the more stronger the more the period length of a LD deviates from 24 h. In the range of resonance about 24 h there is a greater flexibility with regard to the phase relation of the maximum values. 6. Activity reacts very sensitive to the differential parameter of the forcing signal. Therefore, no phaseangle difference occurs between forcing and forced signal. Moreover, the system needs no swing-in time to become entrained when starting a LD. 7. After transition from LD to DD (= constant darkness) the forced signal does not die away immediately, but damps out within one or a few cycles with decreasing amplitude and unchanged frequency. 8. In nearly all applied LDs a non-synchronized circadian rhythm can be observed in addition to the entrained frequency, which is dominant. 9. Also, in DD a freerunning circadian rhythm is detectable. 10. We suggest the model that first a passive system with a nearly unlimited range of entrainment controls activity. In contrary to extremely passive systems, it is able to oscillate. Moreover, it acts like a linear system with respect to frequency transfer: In the tested cases, output and input frequency are equal. In addition, activity is under control of an endogenous circadian oscillator. Its effects are overlapped under forcing conditions, but they become obvious under constant conditions. Furthermore, nonstationary processes are features of this circadian rhythm. The proper­ ties of a passive and a circadian system alone do not explain the flexible patterns in the range of resonance. Therefore, a time-dependent controller is demanded to control the phase relation of the maxima.

Exogenous and Endogenous Control of Swimming Activity in Astyanax mexicanus (Characidae, Pisces) by Direct Light Response and by a Circadian Oscillator II. Features of Time-Controlled Behaviour of a Cave Population and their Comparison to a Epigean Ancestral Form

1982 ◽  
Vol 37 (11-12) ◽  
pp. 1266-1273 ◽  
Author(s):  
Wilhelmine Erckens ◽  
Wolfgang Martin
Keyword(s):  
Surface Activity ◽  
Activity Patterns ◽  
Light Response ◽  
Swimming Activity ◽  
Period Length ◽  
Circadian Oscillator ◽  
Constant Darkness ◽  
Control Activity ◽  
Astyanax Mexicanus ◽  
River Fish

Abstract 1. The swimming activity of 6 specimens of the Pachon cave form of Astyanax mexicanus was tested with regard to its time control under various light-dark(LD)cycles and constant conditions, and it is compared to that of a river form. 2. In general, activity is entrainable by all applied LDs, but even if the amplitude of a forcing signal increases the signal energies are lower than in the river fish. 3. In case of entrainment the maximum values of surface activity correspond to the dark phases, those of bottom activity to the light phases of a LD. Flexible patterns -as often observed in the river form in the range of resonance about 24 h - are very seldom. Furthermore, disturbances of­ ten occur in the entrainment of one activity form, or one form runs arrhythmic while the other is still entrained. 4. The activity answers to changing environmental conditions are not as uniformly quick as in the river fish. But the system hardly needs a swing-in time to become entrained when a LD starts. 5. After transition from LD to DD (= constant darkness) the entrained rhythms disappear immediately. 6. In no LD with a period length differing from 24 h a circadian rhythm can be observed in addition to the entrained frequency. 7. These results show that the passive system of the river form has developped into an extremely passive one being unable to oscillate and thus has become simplified during regressive evolution. Concerning the circadian oscillator of the epigean ancestor, it was also subjected to regression, but it has not been completely lost. After a LD with a period length about 24 h the circadian oscillator is able to act as a stable system, clearly shown by the freerunning circadian rhythms of surface activity. But out of this range the oscillator is unable to control activity. In DD after all other LDs activity patterns are arrhythmic.

A circadian rhythm in the locomotive behaviour of the giant garden slug Limax maximus

1977 ◽  
Vol 66 (1) ◽  
pp. 47-64
Author(s):  
P. G. Sokolove ◽  
C. M. Beiswanger ◽  
D. J. Prior ◽  
A. Gelperin
Keyword(s):  
Circadian Rhythm ◽  
Locomotor Activity ◽  
Phase Angle ◽  
Circadian Rhythmicity ◽  
Constant Darkness ◽  
Light Cycle ◽  
Circadian Activity ◽  
Locomotor Rhythm ◽  
Activity Peak ◽  
Limax Maximus

The locomotor activity of the garden slug Limax maximus was examined for components of circadian rhythmicity. Behavioural (running wheel) studies clearly demonstrated that the activity satisfies the principal criteria of circadian rhythmicity. In constant darkness at a constant temperature, the locomotor activity freeran with a period of about 24 h (range 23-6-24-6 h). The rhythm was also expressed in constant light with a period for individual slugs that tended to be shorter in LL than in DD. The period of the rhythm was temperature compensated (11–5-21-5 degrees C) with a Q10 approximately equal to 1–00. The locomotor rhythm could be entrained to 24 h LD cycles such that the circadian activity peak occurred during the dark. The phase angle between the onset of activity and lights-off was not fixed, but was a function of the photoperiod of the entraining light cycle.

Effect of somatostatin on circadian rhythms of firing and 2-deoxyglucose uptake in rat suprachiasmatic slices

1993 ◽  
Vol 265 (5) ◽  
pp. R1199-R1204 ◽  
Author(s):  
T. Hamada ◽  
S. Shibata ◽  
A. Tsuneyoshi ◽  
K. Tominaga ◽  
S. Watanabe
Keyword(s):  
Circadian Rhythm ◽  
Vasoactive Intestinal Polypeptide ◽  
Phase Changes ◽  
Circadian Clocks ◽  
Constant Darkness ◽  
Phase Resetting ◽  
Firing Activity ◽  
Light Pulses ◽  
Circadian Time

In mammals, the suprachiasmatic nucleus (SCN) of the hypothalamus appears to act as a circadian clock. The SCN vasoactive intestinal polypeptide-like immunoreactive neurons, which may act to mediate photic information in the SCN, receive input from neurons immunoreactive for somatostatin (SST). Therefore we investigated the role of SST as a transmitter for entrainment by analyzing the phase-resetting effect of SST on the circadian rhythm of SCN firing activity. Perfusion of SST increased 2-deoxyglucose uptake at circadian time (CT) 18, but not at CT6. A 1-h or 15-min treatment with SST produced phase delays when it was administered at CT13-14 and phase advances at CT22-23. Thus SST-induced phase changes are similar to those for light pulses to animals under constant darkness. The present findings suggest that SST is a transmitter for mediating information of entrainment to circadian clocks within the SCN.

A circadian rhythm of behavioural thermoregulation in a freshwater gastropod, Helisoma trivolis

1980 ◽  
Vol 58 (11) ◽  
pp. 2152-2155 ◽  
Author(s):  
Martin Kavaliers
Keyword(s):  
Circadian Rhythm ◽  
Constant Darkness ◽  
Dark Phase ◽  
Behavioural Thermoregulation ◽  
Dark Cycle ◽  
Preferred Temperature ◽  
Temperature Selection ◽  
Freshwater Gastropod ◽  
Free Running ◽  
Maximum Temperatures

The behaviour of the aquatic gastropod Helisoma trivolis was examined in a thermal gradient. Under a 12 h light: 12 h dark cycle gastropods displayed a diel rhythm of preferred temperature selection. Maximum temperatures (21–22 °C) were selected during the dark phase and minimum temperatures (17–18 °C) were selected during the light phase of the light–dark cycle. Under constant darkness temperature selection continued as an endogenous free-running circadian rhythm of behavioural thermoregulation.

Effects of chronic lithium, clorgyline, imipramine, fluphenazine and constant darkness on the α-melanotropin content and circadian rhythm in rat brain

1982 ◽  
Vol 85 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Thomas L. O'Donohue ◽  
Anna Wirz-Justice ◽  
Marian S. Kafka ◽  
Dieter Naber ◽  
Iain C. Campbell ◽  
...  
Keyword(s):  
Circadian Rhythm ◽  
Rat Brain ◽  
Constant Darkness

Altered hormone levels and circadian rhythm of activity in the WKY rat, a putative animal model of depression

2001 ◽  
Vol 281 (3) ◽  
pp. R786-R794 ◽  
Author(s):  
Leah C. Solberg ◽  
Susan Losee Olson ◽  
Fred W. Turek ◽  
Eva Redei
Keyword(s):  
Circadian Rhythm ◽  
Wistar Rats ◽  
Depressive Disorders ◽  
Rat Plasma ◽  
Thyroid Stimulating Hormone ◽  
Constant Darkness ◽  
Wky Rats ◽  
Animal Model Of Depression ◽  
Wistar Kyoto ◽  
Free Running Period

The Wistar Kyoto (WKY) rat is hyperreactive to stress and exhibits depressive-like behavior in several standard behavioral tests. Because patients with depressive disorders often exhibit disruptions in the circadian rhythm of activity, as well as altered secretory patterns of the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-thyroid hormones, we tested the hypothesis that these phenomena occur in the WKY rat. Plasma ACTH and corticosterone levels remained significantly higher after the diurnal peak for several hours in WKY rats relative to Wistar rats. Also, plasma levels of thyroid-stimulating hormone were significantly higher in WKY relative to Wistar rats across the 24-h period, despite normal or slightly higher levels of 3,5,3′-triiodothyronine. In addition, under constant darkness conditions, WKY rats exhibited a shorter free running period and a decreased response to a phase-delaying light pulse compared with Wistar rats. In several ways these results are similar to those seen in other animal models of depression as well as in depressed humans, suggesting that the WKY rat could be used to investigate the genetic basis for these abnormalities.

Circadian rhythms and depression: effects of exercise in an animal model

1999 ◽  
Vol 276 (1) ◽  
pp. R152-R161 ◽  
Author(s):  
Leah C. Solberg ◽  
Teresa H. Horton ◽  
Fred W. Turek
Keyword(s):  
Circadian Rhythms ◽  
Depressive Disorders ◽  
Activity Rhythm ◽  
Sucrose Solution ◽  
Forced Swim Test ◽  
Total Activity ◽  
Constant Darkness ◽  
Activity Rhythms ◽  
Running Wheels ◽  
And Control

There is a clear link between altered circadian rhythms and depressive disorders, although the nature of this relationship is unknown. In addition, exercise affects both mood and alters clock function. To investigate the relationship between circadian rhythms, depression, and exercise, 3-wk-old mice housed on a 12:12-h light-dark cycle were exposed to chronic stress (CS) for 6 wk before being placed into constant darkness (DD). One-half of both the control and stressed mice were given access to a running wheel. Stressed mice consumed significantly less of a 2% sucrose solution during CS and exhibited a significant increase in immobility in the forced swim test 3 wk after the termination of stress relative to control mice. These effects were more pronounced in mice without running wheels. Stressed mice also exhibited altered percent distribution of total activity and increased fragmentation of daily activity rhythms during CS relative to control mice. Alterations in percent distribution were more pronounced in animals without running wheels. No activity rhythm changes were seen in DD, and there were no differences in light-induced phase shifts between stressed and control mice. These results suggest that CS causes long-term depressive-like symptoms but does not have long-lasting effects on activity rhythms. These changes were more pronounced in mice without running wheels, suggesting that exercise may protect against the harmful effects of stress.

Visual receptor cycle in normal and period mutant Drosophila: Microspectrophotometry, electrophysiology, and ultrastructural morphometry

1992 ◽  
Vol 9 (2) ◽  
pp. 125-135 ◽  
Author(s):  
De-Mao Chen ◽  
J. Scott Christianson ◽  
Randall J. Sapp ◽  
William S. Stark
Keyword(s):  
Circadian Rhythm ◽  
Visual Pigment ◽  
Constant Darkness ◽  
Wild Type ◽  
Dark Cycle ◽  
Light Onset ◽  
Cross Sectional ◽  
Ultrastructural Morphometry ◽  
Em Morphometry ◽  
Visual Receptor

AbstractVisual pigment, sensitivity, and rhabdomere size were measured throughout a 12-h light/12-h dark cycle in Drosophila. Visual pigment and sensitivity were measured during subsequent constant darkness [dark/dark (D/D)]. MSP (microspectrophotometry) and the ERG (electroretinogram) revealed a cycling of visual pigment and sensitivity, respectively. A visual pigment decrease of 40% was noted at 4 h after light onset that recovered 2–4 h later in white-eyed (otherwise wild-type, w per+) flies. The ERG sensitivity [in w per+ flies in light/dark (L/D)] decreased by 75% at 4 h after light onset, more than expected if mediated by visual pigment (MSP) changes alone. ERG sensitivity begins decreasing 8 h before light onset while decreases in visual pigment begin 2 h after light onset. These cycles continue in constant darkness (D/D), suggesting a circadian rhythm. White-eyed period (per) mutants show similar cycles of visual pigment level and sensitivity in L/D; per's alterations, if any on the D/D cycles were subtle. The cross-sectional areas of rhabdomeres in w per+ were measured using electron micrographic (EM) morphometry. Area changed little through the L/D cycle.

REGULATION BY THE PITUITARY GLAND OF CIRCADIAN RHYTHMS IN THE HAMSTER

1980 ◽  
Vol 85 (1) ◽  
pp. 17-25 ◽  
Author(s):  
IRVING ZUCKER ◽  
CATHERINE P. CRAMER ◽  
E. L. BITTMAN
Keyword(s):  
Circadian Rhythm ◽  
Locomotor Activity ◽  
Pituitary Gland ◽  
Activity Cycle ◽  
Active Phase ◽  
Circadian Oscillation ◽  
Constant Darkness ◽  
Subjective Night ◽  
The Difference

SUMMARY Locomotor activity of male hamsters was recorded during long-term exposure to constant light (LL), constant darkness (DD) and during entrainment (modification of a circadian rhythm) to a 14 h light: 10 h darkness photoperiod (14L: 10D). In LL the period of the activity cycle was substantially longer in hypophysectomized than in control animals. This difference persisted during tests in DD. Although hypophysectomy reduced the duration of the active phase in some hamsters, overall the difference between the groups was not significant. The phase angle of onset of activity in 14L: 10D was not affected by hypophysectomy. Hypophysectomized female hamsters tested in DD had activity rhythms whose periods were longer than those of control animals; they were also significantly less active than corresponding controls during the first 4 h of the subjective night but the duration of the active phase did not differ significantly between the groups. These results suggest that hormones of the pituitary-gonadal axis modulate the period of circadian oscillation.

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