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Glickman GL, Harrison EM, Elliott JA, Gorman MR. Increased photic sensitivity for phase resetting but not melatonin suppression in Siberian hamsters under short photoperiods. Horm Behav 2014; 65:301-7. [PMID: 24440383 PMCID: PMC3963461 DOI: 10.1016/j.yhbeh.2014.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 01/08/2014] [Accepted: 01/10/2014] [Indexed: 11/19/2022]
Abstract
Light regulates a variety of behavioral and physiological processes, including activity rhythms and hormone secretory patterns. Seasonal changes in the proportion of light in a day (photoperiod) further modulate those functions. Recently, short (SP) versus long days (LP) were found to markedly increase light sensitivity for phase shifting in Syrian hamsters. To our knowledge, photoperiod effects on light sensitivity have not been studied in other rodents, nor is it known if they generalize to other circadian responses. We tested whether photic phase shifting and melatonin suppression vary in Siberian hamsters maintained under LP or SP. Select irradiances of light were administered, and shifts in activity were determined. Photic sensitivity for melatonin suppression was examined in a separate group of animals via pulses of light across a 4 log-unit photon density range, with post-pulse plasma melatonin levels determined via RIA. Phase shifting and melatonin suppression were greater at higher irradiances for both LP and SP. The lower irradiance condition was below threshold for phase shifts in LP but not SP. Melatonin suppression did not vary by photoperiod, and the half saturation constant for fitted sigmoid curves was similar under LP and SP. Thus, the photoperiodic modulation of light sensitivity for phase shifting is conserved across two hamster genera. The dissociation of photoperiod effects on photic phase shifting and melatonin suppression suggests that the modulation of sensitivity occurs downstream of the common retinal input pathway. Understanding the mechanistic basis for this plasticity may yield therapeutic targets for optimizing light therapy practices.
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Affiliation(s)
- G L Glickman
- University of California, San Diego, Department of Psychology, Center for Chronobiology, 9500 Gilman Drive, La Jolla, CA 92093, USA.
| | - E M Harrison
- University of California, San Diego, Department of Psychology, Center for Chronobiology, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - J A Elliott
- University of California, San Diego, Department of Psychology, Center for Chronobiology, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - M R Gorman
- University of California, San Diego, Department of Psychology, Center for Chronobiology, 9500 Gilman Drive, La Jolla, CA 92093, USA
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2
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Cassone VM. Avian circadian organization: a chorus of clocks. Front Neuroendocrinol 2014; 35:76-88. [PMID: 24157655 PMCID: PMC3946898 DOI: 10.1016/j.yfrne.2013.10.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 07/18/2013] [Accepted: 10/09/2013] [Indexed: 12/24/2022]
Abstract
In birds, biological clock function pervades all aspects of biology, controlling daily changes in sleep: wake, visual function, song, migratory patterns and orientation, as well as seasonal patterns of reproduction, song and migration. The molecular bases for circadian clocks are highly conserved, and it is likely the avian molecular mechanisms are similar to those expressed in mammals, including humans. The central pacemakers in the avian pineal gland, retinae and SCN dynamically interact to maintain stable phase relationships and then influence downstream rhythms through entrainment of peripheral oscillators in the brain controlling behavior and peripheral tissues. Birds represent an excellent model for the role played by biological clocks in human neurobiology; unlike most rodent models, they are diurnal, they exhibit cognitively complex social interactions, and their circadian clocks are more sensitive to the hormone melatonin than are those of nocturnal rodents.
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Affiliation(s)
- Vincent M Cassone
- Department of Biology, University of Kentucky, Lexington, KY 40506, United States.
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3
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Laakso M, Porkka‐Heiskanen T, Stenberg D, Alila A, Hätönen T. Suppression of human melatonin by light over the course of the rising phase of the synthesis. BIOL RHYTHM RES 2008. [DOI: 10.1080/09291019409360273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Maija‐Liisa Laakso
- a Department of Physiology , University of Helsinki , P.O. Box 9, 00014, Finland Fax:
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4
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Zawilska JB, Lorenc A, Berezínska M, Vivien-Roels B, Pévet P, Skene DJ. Photoperiod-Dependent Changes in Melatonin Synthesis in the Turkey Pineal Gland and Retina. Poult Sci 2007; 86:1397-405. [PMID: 17575188 DOI: 10.1093/ps/86.7.1397] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effect of photoperiod on melatonin content and the activity of the melatonin-synthesizing enzymes, namely, serotonin N-acetyltransferase (AANAT) and hydroxyindole-O-methyltransferase, were investigated in the pineal gland and retina of turkeys. The birds were adapted to 3 different lighting conditions: 16L:8D (long photoperiod), 12L:12D (regular photoperiod), and 8L:16D (short photoperiod). Pineal, retinal, and plasma melatonin concentrations oscillated with a robust diurnal rhythm, with high values during darkness. The duration of elevated nocturnal melatonin levels in the turkey pineal gland, retina, and plasma changed markedly in response to the length of the dark phase, being longest during the short photoperiod with 16 h of darkness. These photoperiodic variations in melatonin synthesis appear to be driven by AANAT, because changes in the activity of this enzyme were closely correlated with changes in melatonin. By contrast, pineal and retinal hydroxyindole-O-methyltransferase activities failed to exhibit any significant 24-h variation in the different photoperiods. A marked effect of photoperiod on the level of melatonin production was also observed. Peak values of melatonin and AANAT activity in the pineal gland (but not in the retina) were highest during the long photoperiod. During the light phase, mean melatonin concentrations in the pineal gland and retina of turkeys kept under the long photoperiod were significantly higher compared with those from birds maintained under the regular and short photoperiods. In addition, mean circulating melatonin levels were lowest in the short photoperiod. Finally, the magnitude of the light-evoked suppression of nighttime pineal AANAT activity was also influenced by photoperiod, with suppression being smallest under the long photoperiod. These findings show that in the turkey, photoperiod plays an important role in regulating the melatonin signal.
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Affiliation(s)
- J B Zawilska
- Centre for Medical Biology, Polish Academy of Sciences, Lodz, 93-232, Poland.
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5
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Moore CB, Siopes TD. Effects of lighting conditions and melatonin supplementation on the cellular and humoral immune responses in Japanese quail Coturnix coturnix japonica. Gen Comp Endocrinol 2000; 119:95-104. [PMID: 10882554 DOI: 10.1006/gcen.2000.7496] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two experiments were conducted to determine the effects of lighting conditions and melatonin supplementation on the cellular and humoral immune responses in Japanese quail. The first experiment was designed to evaluate differing light regimes as immune modulators in both adult and juvenile quail. The cellular and humoral immune responses were determined for three lighting conditions; short days (8:16LD), long days (16:8LD), and constant light (LL). In the second experiment, melatonin was administered in varying doses to adult quail placed in LL. The doses used in this experiment were 0.0, 0.5, 5.0, and 50.0 microg/ml melatonin given in the drinking water for 16 h per day for 2 weeks. The cellular and humoral immune responses were evaluated after 1 week of melatonin treatment. In both experiments, a cutaneous basophil hypersensitivity reaction to phytohemagglutinin (PHA-P) was measured to evaluate the cellular immune response. To evaluate the humoral immune response, primary antibody titers were calculated 7 days postintravenous injection with a Chukar red blood cell suspension. In the adult birds of experiment 1, both the 8:16LD and 16:8LD treatments produced similar cellular and humoral immune responses but these responses were significantly greater than those observed in LL. The juvenile birds held under 8:16LD also had significantly greater cellular and humoral immune responses as compared to juvenile birds held in LL. In experiment 2, there was a clear melatonin dose response on immune function in LL. The humoral immune response increased to a peak at the 5.0 microg/ml dose while the cellular immune response increased across all dose levels. From the present study it was clear that quail placed in daily light-dark cycles (LD), possessing a diurnal rhythm of melatonin, had significantly elevated immune responses as compared to those birds in LL. Furthermore, melatonin supplemented to birds exposed to LL was immuno-enhancing. This suggests that melatonin may be a mediator of the differences seen between LD and LL lighting conditions and may have important immune modulating properties.
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Affiliation(s)
- C B Moore
- Department of Poultry Science, North Carolina State University, Raleigh, North Carolina, 27695-7608, USA
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6
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Whitfield-Rucker M, Cassone VM. Photoperiodic regulation of the male house sparrow song control system: gonadal dependent and independent mechanisms. Gen Comp Endocrinol 2000; 118:173-83. [PMID: 10753579 DOI: 10.1006/gcen.2000.7455] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The primary and secondary sexual characteristics of many species of passerine birds undergo dramatic seasonal variation in response to the change in the length of photoperiod. Among the many physiological processes that undergo seasonal changes, bird song and the song control system underlying it undergo similar seasonal variation in size and function. The mechanisms of this seasonal variation are largely unknown but are at least partially due to steroidal action from the gonads. The present study determined the relative roles played by the gonads and the photoperiodic timing system that controls gonadal development on song control nuclei in the brain of the male house sparrow, Passer domesticus. Sparrows maintained in short photoperiods (SD) possessed small regressed testes. Transfer to long photoperiods (LD) for 6 weeks evoked a dramatic increase in testes size, but, after 20 weeks under the same conditions (LDLD), testes completely collapsed. Song control nuclei HVC and RA were smaller in SD than in LD but regressed only moderately in LDLD. Castration of sparrows in SD reduced the amplitude of the seasonal variation but did not completely abolish it. The data support the view that the song control system of the house sparrow is regulated by the photoperiodic timing system independently of gonadal influence, but that the gonads augment seasonal regulation of song, presumably via steroidal hormone secretion.
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Affiliation(s)
- M Whitfield-Rucker
- Department of Biology, Texas A&M University, College Station, Texas, 77843, USA
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7
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Zeman M, Výboh P, Juráni M, Lamosová D, Kostal L, Bilcík B, Blazícek P, Jurániová E. Effects of exogenous melatonin on some endocrine, behavioural and metabolic parameters in Japanese quail Coturnix coturnix japonica. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. COMPARATIVE PHYSIOLOGY 1993; 105:323-8. [PMID: 8101160 DOI: 10.1016/0300-9629(93)90215-p] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Melatonin administration in drinking water (5 micrograms/ml) to Japanese quail resulted in a 20-fold increase of plasma melatonin levels in comparison with the control, day time concentration (0.34 +/- 0.05 vs 6.88 +/- 1.10 nmol/l). 2. Plasma triiodothyronine levels increased (5.8 +/- 0.93 vs 7.97 +/- 0.64 nmol/l), corticosterone decreased (28.04 +/- 3.42 vs 15.96 +/- 2.56 nmol/l) and no significant changes were recorded in thyroxine concentration after the treatment. 3. A higher occurrence of sleeping and lower occurrence of pecking were found in melatonin treated quail. 4. Abdominal fat deposition as well as the content of total lipids in the breast muscle and triacylglycerols in plasma were decreased in treated birds indicating an inhibitory effect of melatonin on lipogenesis. 5. Melatonin increased RNA content in the breast muscle but did not affect plasma glucose concentration and body weight.
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Affiliation(s)
- M Zeman
- Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Slovakia
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8
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Cockrem JF. Circadian rhythms of plasma melatonin in the Adelie penguin (Pygoscelis adeliae) in constant dim light and artificial photoperiods. J Pineal Res 1991; 11:63-9. [PMID: 1757886 DOI: 10.1111/j.1600-079x.1991.tb00457.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The response of plasma melatonin in Adelie penguins (Pygoscelis adeliae) to constant dim light and to light/dark cycles was measured to determine the capacity of the pineal gland to secrete melatonin after exposure to continuous daylight for 2 months. Penguins were moved in mid-summer from the natural photoperiod to either constant dim light (n = 10), to a 12L:12D light/dark cycle (n = 5), or to a 12L:12D light/dark cycle with a 30 min light pulse (50-155 lux) on the third (n = 4) or sixth (n = 5) "night." Blood samples were collected regularly through cannulae for up to 33 h. The birds in dim light were sampled after 2 days, with samples obtained over at least 24 h from 7 birds. Three of these birds had melatonin rhythms (peak levels 66.7-130.2 pg/ml) whereas the other 4 birds had constant low levels (less than 44 pg/ml). The phase of the rhythm was similar for all 3 birds. This is consistent with the pacemaker that regulates the circadian rhythm of melatonin secretion being entrained to a period of 24 h when the penguins were exposed to the natural photoperiod. Mean melatonin levels (42.7 +/- 2.5 pg/ml) were elevated compared to those previously reported in penguins under natural daylight. All penguins held under a 12L:12D light/dark cycle had melatonin rhythms. The phase and form of these rhythms were similar to those reported for other birds, and they appeared to be circadian rhythms entrained by the light/dark cycle.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J F Cockrem
- Ecology Division, Department of Scientific and Industrial Research, Lower Hutt, New Zealand
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9
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Effects of light and an alpha-2-adrenergic agonist on serotonin N-acetyltransferase activity in chick pineal gland. J Neural Transm (Vienna) 1990; 82:119-29. [PMID: 1977416 DOI: 10.1007/bf01245168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Pineal serotonin N-acetyltransferase (NAT) is the enzyme that catalyzes the production of N-acetylserotonin from serotonin and is the rate limiting step in the biosynthesis of melatonin in the chick pineal gland. Chick pineal NAT activity is decreased by light and by noradrenergic agents that act at the alpha-2-adrenergic receptor. Light-induced inhibition of nocturnal NAT activity can be demonstrated by exposing 4-day-old chicks to light, or by exposing pineal gland explants cultured in vitro either to light or to UK 14,304 (an alpha-2-adrenergic agonist). The inhibition by either light or UK 14,304 is preceded by a transient, but consistent rise in NAT activity. The paradoxical, transient light-induced rise in enzyme activity is mimicked by UK 14,304 which suggests a similarity in mechanisms of light and adrenergic signal transduction associated with the regulation of NAT activity.
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10
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Binkley S, Mosher K, White BH. Photoperiod modifies daily maps of light and dark sensitivity for N-acetyltransferase activity in pineal glands of 3-week old Gallus domesticus. J Comp Physiol B 1989; 159:37-42. [PMID: 2738201 DOI: 10.1007/bf00692681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
N-acetyltransferase (NAT) activity in pineal glands exhibits a circadian rhythm with peak activity occurring in the dark-time. We previously showed that in Gallus domesticus chicks pretreated with LD12:12, NAT activity was increased by dark exposure (peak dark sensitivity occurred during the expected dark-time) or decreased by light at night (peak light sensitivity occurred early in the night during the time of dark sensitivity). In this study we mapped dark sensitivity vs time (for NAT activity increase in response to 2 h dark pulses), and light sensitivity vs time (for NAT activity decrease in response to 10 min or 30 min light pulses) over a cycle for 3-week old chicks, Gallus domesticus, pretreated with long (LD16:8) or short photoperiod (LD8:16). Sensitivity to light was increased in the second 8 h after L/D by LD8:16. Sensitivity to dark was increased in the first 8 h after L/D by LD16:8.
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Affiliation(s)
- S Binkley
- Biology Department, Temple University, Philadelphia, Pennsylvania 19122
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11
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Zeman M, Illnerová H. Rapid adjustment of the pineal N-acetyltransferase rhythm to change from long to short photoperiod in the Japanese quail (Coturnix coturnix japonica). J Pineal Res 1988; 5:565-71. [PMID: 3225739 DOI: 10.1111/j.1600-079x.1988.tb00799.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The dynamics of adjusting the pineal N-acetyltransferase rhythm from long to short photoperiod was assessed in the Japanese quail (Coturnix coturnix japonica). The transition from LD 16:8 to LD 8:16 was accomplished by symmetrical prolongation of the dark period. In LD 16:8, the period of elevated nocturnal activity lasted approximately 7 hours. During the first prolonged night, the evening N-acetyltransferase rise advanced by almost 3 hours relative to the rise in LD 16:8 and occurred at the same time as during the 3rd, 7th, and 14th day after the transition. The morning N-acetyltransferase decline did not shift during the first long night; during the third night it was delayed relative to the decline in LD 16:8 by more than 2 hours and occurred at the same time as during the 7th and 14th night following the LD 16:8 to LD 8:16 transition. Three, 7, and 14 days after the transition, the period of elevated N-acetyltransferase activity lasted approximately 12 hours. Hence extension of the N-acetyltransferase rhythm profile proceeded first into the evening and then only into the morning hours, and it was accomplished within 2 to 3 days.
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Affiliation(s)
- M Zeman
- Poultry Research Institute Ivanka pri Dunaji, Slovak Academy of Sciences, Czechoslovakia
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12
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Creighton JA, Rudeen PK. Effects of acute ethanol administration on nocturnal pineal serotonin N-acetyltransferase activity. Life Sci 1988; 43:2007-14. [PMID: 3210898 DOI: 10.1016/0024-3205(88)90574-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The effect of acute ethanol administration on pineal serotonin N-acetyltransferase (NAT) activity, norepinephrine and indoleamine content was examined in male rats. When ethanol was administered in two equal doses (2 g/kg body weight) over a 4 hour period during the light phase, the nocturnal rise in NAT activity was delayed by seven hours. The nocturnal pineal norepinephrine content was not altered by ethanol except for a delay in the reduction of NE with the onset of the following light phase. Although ethanol treatment led to a significant reduction in nocturnal levels of pineal serotonin content, there was no significant effect upon pineal content of 5-hydroxyindoleacetic acid (5-HIAA). The data indicate that ethanol delays the onset of the rise of nocturnal pineal NAT activity.
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Affiliation(s)
- J A Creighton
- Department of Anatomy, School of Medicine, University of Missouri, Columbia 65212
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Sig�enza AF, Recio JM, Sanchez M, Agapito MT. Endogenous regulation of the pineal melatonin secretion inGallus domesticus. J Comp Physiol B 1988. [DOI: 10.1007/bf00695337] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Binkley S, Mosher K, White BH. Circadian rhythm in pineal N-acetyltransferase activity: rapid phase reversal and response to shorter than 24-hour cycles (IV). J Neurochem 1987; 49:828-33. [PMID: 3612127 DOI: 10.1111/j.1471-4159.1987.tb00968.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
N-Acetyltransferase (NAT) is an enzyme whose rhythmic activity in the pineal gland and retina is responsible for circadian rhythms in melatonin. The NAT activity rhythm has circadian properties such as persistence in constant conditions and precise control by light and dark. Experiments are reported in which chicks (Gallus domesticus), raised for 3 weeks in 12 h of light alternating with 12 h of dark (LD12:12), were exposed to 1-3 days of light-dark treatments during which NAT activity was measured in their pineal glands. (a) In LD12:12, NAT activity rose from less than 4.5 nmol/pineal gland/h during the light-time to 25-50 nmol/pineal gland/h in the dark-time. Constant light (LL) attenuated the amplitude of the NAT activity rhythm to 26-45% of the NAT activity cycle in LD12:12 during the first 24 h. (b) The timing of the increase in NAT activity was reset by the first full LD12:12 cycle following a 12-h phase shift of the LD12:12 cycle (a procedure that reversed the times of light and dark by imposition of either 24 h of light or dark). This result satisfies one of the criteria for NAT to be considered part of a circadian driving oscillator. (c) In less than 24-h cycles [2 h of light in alternation with 2 h of dark (LD2:2), 4 h of light in alternation with 4 h of dark (LD4:4), and 6 h of light in alternation with 6 h of dark (LD6:6)], NAT activity rose in the dark during the chicks' previously scheduled dark-time but not the previously scheduled light-time of LD12:12. In a cycle where 8 h of light alternated with 8 h of dark (LD8:8), NAT activity rose in both 8-h dark periods, even though the second one fell in the light-time of the prior LD12:12 schedule.(ABSTRACT TRUNCATED AT 250 WORDS)
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Liou SS, Cogburn LA, Biellier HV. Photoperiodic regulation of plasma melatonin levels in the laying chicken (Gallus domesticus)1. Gen Comp Endocrinol 1987; 67:221-6. [PMID: 3623076 DOI: 10.1016/0016-6480(87)90151-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Plasma melatonin profiles were determined in laying chickens maintained on either a 16L:8D or a 20L:4D light-dark cycle (LDC). The range of plasma melatonin concentrations was low during the light period (40-100 pg/ml) and higher during the dark period (150-390 pg/ml). Compared to the light period, plasma concentrations of melatonin were 4- to 5-fold higher (P less than 0.05) during the dark period. The amplitude of melatonin concentrations was greater when hens were held under a short dark period (4.6-fold, 20L:4D) than when hens were exposed to a 16L:8D LDC (3.8-fold). In the laying chicken, a broad peak in concentration of plasma melatonin was found in the dark period. It was different from that previously reported in the chick. Since the time of oviposition in the hen occurs in a limited period after the onset of darkness in a LDC, a modified physiological function of melatonin for birds of different ages may account for the difference in the nocturnal pattern of plasma melatonin. The elevated level of plasma melatonin in the dark period of a LDC is considered to be essential for regulating the time of oviposition in the laying chicken under a particular LDC.
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Binkley S, Mosher K, White BH. Circadian rhythm in pineal N-acetyltransferase activity: phase shifting by dark pulses (III). J Neurochem 1985; 45:875-8. [PMID: 4031867 DOI: 10.1111/j.1471-4159.1985.tb04075.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
N-Acetyltransferase (NAT) is an enzyme whose rhythmic activity in the pineal gland and retina is thought to be responsible for melatonin circadian rhythms. The enzyme has circadian properties--its rhythm persists in constant conditions, and it is precisely controlled by light and dark. Experiments are reported in which 4-h light or dark pulses were imposed on chicks (Gallus domesticus) over a 24-h period. Pineal NAT profiles were measured during and subsequent to the pulses. The phase of the NAT cycle following pulses was plotted to obtain phase-response curves. Light pulses produced a maximum phase shift (advance of 5 h) 8 h after the expected time of lights-out; dark pulses produced a maximum phase shift (advance of 4 h) 3 h after the expected time of lights-out. Maximum phase delays (-2 h) occurred 1-2 h after the expected lights-out for light pulses and 8 h after expected lights-on for dark pulses.
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Binkley S, Mosher K. Prior light alters the circadian clock in the chick pineal gland. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1984; 232:551-6. [PMID: 6520586 DOI: 10.1002/jez.1402320322] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
N-Acetyltransferase activity (NAT) exhibits a circadian rhythm in the pineal gland and retinas of chickens and is responsible for melatonin circadian rhythms. Chick pineal gland NAT was measured in vivo and/or in vitro after light-dark cycles and after pretreatments with short photoperiod, long photoperiod, and constant light. Prior lighting changed the shape (phase, amplitude, and duration) of the rhythm in vivo. Some of the alterations are "programmed" into the pineal gland because they were observed in vitro in pineal glands from chicks similarly exposed to lighting pretreatments.
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Abstract
N-Acetyltransferase (NAT) is an enzyme whose rhythmic activity in the pineal gland and retina is thought responsible for melatonin circadian rhythms. The enzyme has properties of a circadian biological clock--its rhythm persists in constant conditions and it is precisely controlled by light and dark. Experiments are reported in which light pulses of 1 to 10 h duration were imposed on chicks during their dark-time. The effect of these pulses upon the NAT was measured and the effect of the pulses on subsequent NAT was also determined. The experiments support the conclusion that the amount and/or duration of dark-time NAT is limited. This finding is interpreted as supporting the idea that a fixed amount of some substance, an initiator, is synthesized during the subjective day.
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Fuchs JL. Effects of pinealectomy and subsequent melatonin implants on activity rhythms in the house finch (Carpodacus mexicanus). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1983. [DOI: 10.1007/bf00612595] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Binkley S. Rhythms in ocular and pineal N-acetyltransferase: a portrait of an enzyme clock. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1983; 75:123-9. [PMID: 6135530 DOI: 10.1016/0300-9629(83)90057-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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21
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Miller CH, Lakin ML, Stott ML, Wenger N, Rosenblatt LS, Winters WD. Effect of isoproterenol upon serotonin N-acetyltransferase (SNAT) activity and melatonin production in the chick pineal gland. Neuropharmacology 1981; 20:1059-65. [PMID: 7322282 DOI: 10.1016/0028-3908(81)90097-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Leonhardt VH. Ependym und Circumventriculäre Organe. HANDBUCH DER MIKROSKOPISCHEN ANATOMIE DES MENSCHEN 1980. [DOI: 10.1007/978-3-642-81358-0_3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Binkley S, Riebman JB, Reilly K. Regulation of pineal rhythms in chickens: N-acetyltransferase activity in homogenates. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C: COMPARATIVE PHARMACOLOGY 1979; 63C:291-6. [PMID: 40740 DOI: 10.1016/0306-4492(79)90076-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Stephens JL, Binkley S. Daily change in pineal N-acetyltransferase activity in a diurnal mammal, the ground squirrel. EXPERIENTIA 1978; 34:1523-4. [PMID: 720495 DOI: 10.1007/bf01932390] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Pineal N-acetyltransferase (NAT) activity in the ground squirrel, a diurnal mammal, was found to have a daily fluctuation with peak activity during the dark time. This same daily change is found in nocturnal mammals and diurnal birds. NAT may play an important role in keeping track of light and dark cycles.
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Binkley S, Riebman JB, Reilly K. Regulation of pineal rhythms in chickens: inhibition of dark-time N-acetyltransferase activity. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C: COMPARATIVE PHARMACOLOGY 1978; 59:165-71. [PMID: 25741 DOI: 10.1016/0306-4492(78)90048-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Abstract
N-Acetyltransferase, an enzyme involved in melatonin production in the pineal gland, exhibits a circadian rhythm in chickens with peak values in the dark-time and low values during the light-time, commencing at lights-on. When pineal glands of chickens killed during the dark-time (with high N-acetyltransferase activity) were organ-cultured, there was a decline in enzyme activity to light-time values. Regardless of the time of the dark at which the chickens were killed, the enzyme activity reached light-time levels at precisely the same time.
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