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Filipovská E, Červená K, Moravcová S, Novotný J, Kyclerová H, Spišská V, Pačesová D, Bendová Z. The effect of the cannabinoid receptor agonist and antagonist on the light-induced changes in the suprachiasmatic nucleus of rats. Neurosci Lett 2019; 703:49-52. [PMID: 30885633 DOI: 10.1016/j.neulet.2019.03.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/28/2019] [Accepted: 03/13/2019] [Indexed: 11/20/2022]
Abstract
The CB1 cannabinoid receptors have been found in the rodent suprachiasmatic nucleus, and their activation suppresses the light-induced phase shift in locomotor rhythmicity of mice and hamsters. Here, we show that the CB1 receptor agonist CP55940 significantly attenuates the light-induced phase delay in rats as well. Furthermore, it blocks the light induction of c-Fos and light-induced downregulation of pERK1/2 in the SCN, and the CB1 antagonist AM251 prevents the photic induction of pERK1/2 and reduces pGSK3β after photic stimulation. Our data suggest that the modulation of the cannabinoid receptor activity may affect the photic entrainment via the setting of the SCN sensitivity to light.
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Affiliation(s)
- Eva Filipovská
- Faculty of Science, Charles University, Prague, Czech Republic
| | - Kateřina Červená
- Faculty of Science, Charles University, Prague, Czech Republic; National Institute of Mental Health, Klecany, Czech Republic
| | - Simona Moravcová
- Faculty of Science, Charles University, Prague, Czech Republic; National Institute of Mental Health, Klecany, Czech Republic
| | - Jiří Novotný
- Faculty of Science, Charles University, Prague, Czech Republic
| | - Hana Kyclerová
- Faculty of Science, Charles University, Prague, Czech Republic
| | | | - Dominika Pačesová
- Faculty of Science, Charles University, Prague, Czech Republic; National Institute of Mental Health, Klecany, Czech Republic
| | - Zdeňka Bendová
- Faculty of Science, Charles University, Prague, Czech Republic; National Institute of Mental Health, Klecany, Czech Republic.
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Greene-Schloesser DM, Van der Zee EA, Sheppard DK, Castillo MR, Gregg KA, Burrow T, Foltz H, Slater M, Bult-Ito A. Predictive validity of a non-induced mouse model of compulsive-like behavior. Behav Brain Res 2011; 221:55-62. [PMID: 21316394 DOI: 10.1016/j.bbr.2011.02.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 01/29/2011] [Accepted: 02/06/2011] [Indexed: 11/26/2022]
Abstract
A key to advancing the understanding of obsessive-compulsive disorder (OCD)-like symptoms is the development of spontaneous animal models. Over 55 generations of bidirectional selection for nest-building behavior in house mice, Mus musculus, resulted in a 40-fold difference in the amount of cotton used for a nest in high (BIG) and low (SMALL) selected lines. The nesting behavior of BIG mice appears to be compulsive-like and has initial face validity as an animal model for OCD in humans. Compulsive-like digging behavior was assessed; BIG male mice buried about three times as many marbles as SMALL male mice, strengthening face validity. Using the open field and elevated plus maze, SMALL male mice showed higher levels of anxiety/fear-like behavior than BIG male mice, indicating that compulsive-like and not anxiety-like behavior was measured. To establish predictive validity, chronic (4 weeks) oral administration of fluoxetine (30, 50 and 100mg/kg/day) and clomipramine (80 mg/kg/day), both effective in treating OCD, significantly reduced compulsive-like nest-building behavior in BIG male mice. Compulsive-like digging behavior was also significantly reduced by chronic oral fluoxetine (30 and 80 mg/kg/day) treatment in BIG male mice. General locomotor activity was not affected by chronic oral fluoxetine (30 and 80 mg/kg/day) treatment; chronic oral treatment with desipramine (30 mg/kg/day), an antidepressant not effective in treating OCD, had no effect on nesting behavior of BIG male mice, strengthening predictive validity. Together, the results indicate that these mice have good face and predictive validity as a non-induced mouse model of compulsive-like behavior relevant to OCD.
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Affiliation(s)
- D M Greene-Schloesser
- Behavioral and Evolutionary Neuroscience Laboratory, Department of Biology and Wildlife & Institute of Arctic Biology, PO Box 756100, University of Alaska Fairbanks, Fairbanks, AK 99775-6100, USA
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3
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Van der Veen DR, Castillo MR, Van der Zee EA, Jansen K, Gerkema MP, Bult-Ito A. Circadian dynamics of vasopressin in mouse selection lines: translation and release in the SCN. Brain Res 2005; 1060:16-25. [PMID: 16198320 DOI: 10.1016/j.brainres.2005.07.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2005] [Revised: 07/25/2005] [Accepted: 07/27/2005] [Indexed: 11/19/2022]
Abstract
Arg8-vasopressin (AVP), a circadian clock-controlled gene product, is released from the hypothalamic suprachiasmatic nuclei (SCN) in mice in a circadian fashion. Previously reported differences in two mouse lines, initially selected for thermoregulatory nest-building behavior (building small nests (S-mice) or big nests (B-mice)) with different circadian organization of behavior and in number of SCN-AVP immunoreactive neurons, were further investigated. We confirmed and expanded the finding that S-mice exhibited constant high levels of SCN-AVP content with no apparent circadian rhythmicity, whereas B-mice had lower numbers of AVP positive cells which varied with time of day. We found that AVP mRNA expression levels at midnight and midday were similar in both lines, as established by in situ hybridization. When AVP transport and release were blocked by colchicine, SCN-AVP immunoreactivity was similar in both lines. This suggests that differences in SCN-AVP content depend on transport or release. Organotypic SCN cultures of B-mice showed more AVP release per neuron than cultures of S-mice. These results reveal that on a mechanistic level the mouse lines differed in transport and/or release of AVP in the SCN, rather than differential regulation of AVP gene transcription or number of AVP immunoreactive neurons.
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Affiliation(s)
- D R Van der Veen
- Department of Chronobiology, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands.
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Tavernier RJ, Largen AL, Bult-Ito A. Circadian organization of a subarctic rodent, the northern red-backed vole (Clethrionomys rutilus). J Biol Rhythms 2005; 19:238-47. [PMID: 15155010 DOI: 10.1177/0748730404264200] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arctic and subarctic environments are exposed to extreme light: dark (LD) regimes, including periods of constant light (LL) and constant dark (DD) and large daily changes in day length, but very little is known about circadian rhythms of mammals at high latitudes. The authors investigated the circadian rhythms of a subarctic population of northern red-backed voles (Clethrionomys rutilus). Both wild-caught and third-generation laboratory-bred animals showed predominantly nocturnal patterns of wheel running when exposed to a 16:8 LD cycle. In LL and DD conditions, animals displayed large phenotypic variation in circadian rhythms. Compared to wheel-running rhythms under a 16:8 LD cycle, the robustness of circadian activity rhythms decreased among all animals tested in LL and DD (i.e., decreased chi-squared periodogram waveform amplitude). A large segment of the population became noncircadian (60% in DD, 72% in LL) within 8 weeks of exposure to constant lighting conditions, of which the majority became ultradian, with a few individuals becoming arrhythmic, indicating highly labile circadian organization. Wild-caught and laboratory-bred animals that remained circadian in wheel running displayed free-running periods between 23.3 and 24.8 h. A phase-response curve to light pulses in DD showed significant phase delays at circadian times 12 and 15, indicating the capacity to entrain to rapidly changing day lengths at high latitudes. Whether this phenotypic variation in circadian organization, with circadian, ultradian, and arrhythmic wheel-running activity patterns in constant lighting conditions, is a novel adaptation to life in the arctic remains to be elucidated.
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Affiliation(s)
- Ronald J Tavernier
- Behavioral and Evolutionary Neuroscience Laboratory, Alaskan Basic Neuroscience Program, Institute of Arctic Biology, University of Alaska Fairbanks, 99775-7000, USA
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Castillo MR, Hochstetler KJ, Tavernier RJ, Greene DM, Bult-Ito A. Entrainment of the master circadian clock by scheduled feeding. Am J Physiol Regul Integr Comp Physiol 2004; 287:R551-5. [PMID: 15155280 DOI: 10.1152/ajpregu.00247.2004] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The master circadian clock, located in the mammalian suprachiasmatic nuclei (SCN), generates and coordinates circadian rhythmicity, i.e., internal organization of physiological and behavioral rhythms that cycle with a near 24-h period. Light is the most powerful synchronizer of the SCN. Although other nonphotic cues also have the potential to influence the circadian clock, their effects can be masked by photic cues. The purpose of this study was to investigate the ability of scheduled feeding to entrain the SCN in the absence of photic cues in four lines of house mouse (Mus domesticus). Mice were initially housed in 12:12-h light/dark cycle with ad libitum access to food for 6 h during the light period followed by 4-6 mo of constant dark under the same feeding schedule. Wheel running behavior suggested and circadian PER2 protein expression profiles in the SCN confirmed entrainment of the master circadian clock to the onset of food availability in 100% (49/49) of the line 2 mice in contrast to only 4% (1/24) in line 3 mice. Mice from line 1 and line 4 showed intermediate levels of entrainment, 57% (8/14) and 39% (7/18), respectively. The predictability of entrainment vs. nonentrainment in line 2 and line 3 and the novel entrainment process provide a powerful tool with which to further elucidate mechanisms involved in entrainment of the SCN by scheduled feeding.
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Affiliation(s)
- Marina R Castillo
- Behavioral and Evolutionary Neuroscience Laboratory, Alaskan Basic Neuroscience Program, Institute of Arctic Biology, PO Box 757000, University of Alaska Fairbanks, Fairbanks, AK 99775-7000, USA.
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Yan L, Hochstetler KJ, Silver R, Bult-Ito A. Phase shifts and Per gene expression in mouse suprachiasmatic nucleus. Neuroreport 2003; 14:1247-51. [PMID: 12824769 PMCID: PMC3275415 DOI: 10.1097/00001756-200307010-00012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In mammals, circadian rhythms controlled by the suprachiasmatic nuclei are entrained by photic stimuli. To investigate the molecular mechanism of photic entrainment, we examined light-induced behavioral phase delays and associated changes in mPer1 and mPer2 gene expression in the suprachiasmatic nuclei of two mouse lines artificially selected for nest-building behavior. Big nest-builders show larger phase delays than small nest-builders. Light-induced mPer1 and mPer2 expression was examined in individual mice previously tested for phase shifting at circadian time 16. Light-induced mPer2 expression was significantly higher in big compared to small nest-builders. No difference was found between lines in light-induced mPer1 expression. The results suggest a more important role for mPer2 than for mPer1 gene expression in behavioral phase delays.
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Affiliation(s)
- Lily Yan
- Department of Psychology, Columbia University, New York, NY 10027
| | - Kelly J. Hochstetler
- Behavioral and Evolutionary Neuroscience Laboratory, Alaskan Basic Neuroscience Program, Institute of Arctic Biology, University of Alaska Fairbanks, P.O. Box 757000, Fairbanks, AK 99775
| | - Rae Silver
- Department of Psychology, Columbia University, New York, NY 10027
- Department of Psychology, Barnard College, New York, NY 10027
- Department of Anatomy and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10027, USA
| | - Abel Bult-Ito
- Behavioral and Evolutionary Neuroscience Laboratory, Alaskan Basic Neuroscience Program, Institute of Arctic Biology, University of Alaska Fairbanks, P.O. Box 757000, Fairbanks, AK 99775
- Corresponding Author:
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Rhodes JS, Garland T, Gammie SC. Patterns of Brain Activity Associated With Variation in Voluntary Wheel-Running Behavior. Behav Neurosci 2003; 117:1243-56. [PMID: 14674844 DOI: 10.1037/0735-7044.117.6.1243] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rodents spontaneously run on wheels, but what underlies variation within and between species is unknown. This study used Fos immunoreactivity to compare brain activity in mice selectively bred for high wheel running (S) versus control (C) mice. Mice ran for 6 days, but on Day 7, half the mice were prevented from running. A strong positive correlation was found between running distance and Fos in the dentate gyrus of C runners that was lost in S runners. In mice prevented from running, Fos was higher in S than in C in the lateral hypothalamus, medial frontal cortex, and striatum. Results implicate specific brain regions in motivation to run and others in control of the intensity of the locomotor behavior itself.
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Affiliation(s)
- Justin S Rhodes
- Department of Zoology, University of Wisconsin-Madison, 53706, USA
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8
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Rieux C, Carney R, Lupi D, Dkhissi-Benyahya O, Jansen K, Chounlamountri N, Foster RG, Cooper HM. Analysis of immunohistochemical label of Fos protein in the suprachiasmatic nucleus: comparison of different methods of quantification. J Biol Rhythms 2002; 17:121-36. [PMID: 12002159 DOI: 10.1177/074873002129002410] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The induction of the proto-oncogene c-fos, and its phosphoprotein product Fos, has been extensively used to study the effects of light on the circadian pacemaker in the suprachiasmatic nucleus (SCN). Experimental approaches to the quantification of Fos induction have mainly been based on immunohistochemistry and subsequent measure of Fos immunoreactivity (IR) in sections of the SCN. In this study, the authors compare several methods of quantification using optical density image analysis or counts of Fos-IR labeled cells. To assess whether optical density measures using image analysis reflect the amount of Fos in brain tissue, the authors developed standards of known concentrations of Fos protein in an agar matrix. The agar standards were sectioned and treated simultaneously with sections of the SCN from animals exposed to different levels of irradiance. Optical density was found to be proportional to the quantity of Fos in the sections, indicating that this measure accurately reflects relative levels of Fos protein induction. Quantification by optical density analysis allows an objective measure in which the various parameters, conditions of illumination, and threshold can be maintained constant throughout the analysis. Counting cells by visual observation is more subjective because threshold values cannot be precisely defined and can vary according to the observer, illumination, degree of label, and other factors. In addition, cell counts involving direct visual observation, automated cell counts, or stereological methods do not take into account the difference in the density of label between cells, thus giving equal weight to lightly or densely stained cells. These measures are more or less weakly correlated with measures of optical density and thus do not accurately reflect the amount of bound Fos protein in the tissue sections. In contrast, labeled surface area as measured by image analysis shows a linear relationship with optical density. The main outcome of this study is that computer-assisted image analysis provides an accurate and rapid method to determine the relative amount of Fos protein in the SCN and the effects of light on intracellular signaling mechanisms involved in the circadian clock.
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Affiliation(s)
- C Rieux
- Institut National de la Santé de la Recherche Médicale Unité 371, Cerveau et Vision, Bron, France
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Bult A, Kobylk ME, Van der Zee EA. Differential expression of protein kinase C betaI (PKCbetaI) but not PKCalpha and PKCbetaII in the suprachiasmatic nucleus of selected house mouse lines, and the relationship to arginine-vasopressin. Brain Res 2001; 914:123-33. [PMID: 11578605 DOI: 10.1016/s0006-8993(01)02821-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The functional significance of the suprachiasmatic nucleus (SCN) in circadian rhythm control of mammals has been well documented. The role of protein phosphorylation mediated by protein kinase C (PKC), however, is not well known. We report the immunocytochemical localization of three Ca(2+)-dependent PKC isoforms (alpha, betaI, betaII) within the SCN of selected house mouse lines that differ in behavioral circadian rhythm parameters. Optical density measurements revealed that the adult mice selected for low levels of nest-building behavior (small nest-builders) had more than threefold higher PKCbetaI immunostaining in the SCN than the mice selected for high levels of nest-building behavior (big nest-builders). A similar twofold difference between the adult small and big nest-builders was observed for the number of PKCbetaI-containing cells in the SCN. The non-selected control lines were intermediate. Ten-day-old pups revealed similar differences in PKCbetaI immunostaining in the SCN between the small and big nest-builders. PKCalpha and PKCbetaII immunostaining in the SCN was not different among the lines. PKCbetaI immunostaining was not different among the selected lines in the lateroanterior hypothalamic nucleus (LA) and the cornu ammonis field 1 (CA1) of the dorsal hippocampus and confirms the specificity of the difference in PKCbetaI immunostaining in the SCN among the selected lines. The significance of these findings is discussed in the context of differences among the lines in arginine-vasopressin (AVP) and light-induced Fos expression in the SCN, behavioral phase-delay responses to 15-min light pulses in constant darkness, and measures of the strength of the circadian activity rhythm expressed.
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Affiliation(s)
- A Bult
- Alaskan Basic Neuroscience Program, Institute of Arctic Biology, University of Alaska Fairbanks, P.O. Box 757000, Fairbanks, AK 99775-7000, USA.
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Canal-Corretger MM, Vilaplana J, Cambras T, Díez-Noguera A. Effect of light on the development of the circadian rhythm of motor activity in the mouse. Chronobiol Int 2001; 18:683-96. [PMID: 11587090 DOI: 10.1081/cbi-100106081] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In previous experiments, we found that rats raised in constant light (LL) manifested a more robust circadian rhythm of motor activity in LL and showed longer phase shifts after a light pulse in constant darkness (DD) than chose raised under constant darkness. In addition, we observed that the effects produced by constant light differed depending on the time of postnatal development in which it was given. These results suggest that both sensitivity to light and the functioning of the circadian pacemaker of the rat could be affected by the environmental conditions experienced during postembryonic development. Thus, the present experiment aimed to study whether postnatal exposure to light could also affect the circadian system of the mouse. Three groups of mice were formed: One group was raised under constant darkness during lactation (DD group), the second under constant light (LL group), and the third under light-dark cycles (LD group). After lactation, the three groups were submitted first to constant light of high intensity, then to LD cycles, and finally to constant darkness. In the DD stage, a light pulse was given. Finally, mice were submitted to constant light of low intensity. We observed that the circadian rhythm of the DD group was more disturbed under constant light than the rhythm of the LL group, and that, when light intensity increased, the period of the rhythm of the DD group lengthened more than that of the LL group. No significant differences among the groups were found in the phase shift induced by the light pulse. Therefore, it appears that DD mice are more sensitive to light than their LL counterparts. However, at present there is no evidence to affirm that the light environment experienced by the mouse during postnatal development affects the circadian pacemaker.
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Affiliation(s)
- M M Canal-Corretger
- Departement de Fisiologia, Divisió IV, Facultat de Farmàcia, Universitat de Barcelona, Spain
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Mahoney M, Bult A, Smale L. Phase response curve and light-induced fos expression in the suprachiasmatic nucleus and adjacent hypothalamus of Arvicanthis niloticus. J Biol Rhythms 2001; 16:149-62. [PMID: 11302557 DOI: 10.1177/074873001129001854] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This article describes the phase response curve (PRC), the effect of light on Fos immunoreactivity (Fos-IR) in the suprachiasmatic nucleus (SCN), and the effect of SCN lesions on circadian rhythms in the murid rodent, Arvicanthis niloticus. In this species, all individuals are diurnal when housed without a running wheel, but running in a wheel induces a nocturnal pattern in some individuals. First, the authors characterized the PRC in animals with either the nocturnal or diurnal pattern. Both groups of animals were less affected by light during the middle of the subjective day than during the night and were phase delayed and phase advanced by pulses in the early and late subjective night, respectively. Second, the authors characterized the Fos response to light at circadian times 5, 14, or 22. Light induced an increase in Fos-IR within the SCN during the subjective night but not subjective day; this effect was especially pronounced in the ventral SCN, where retinal inputs are most concentrated, but was also evident in other regions. Both light and time influenced Fos-IR within the lower subparaventricular area. Third, SCN lesions caused animals to become arrhythmic when housed in a light-dark cycle as well as constant darkness. In summary, Arvicanthis appear to be very similar to nocturnal rodents with respect to their PRC, temporal patterns of light-induced Fos expression in the SCN, and the effects of SCN lesions on activity rhythms.
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Affiliation(s)
- M Mahoney
- Zoology Department, Michigan State University, East Lansing 48824, USA
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Lemmer B, Hauptfleisch S, Witte K. Loss of 24 h rhythm and light-induced c-fos mRNA expression in the suprachiasmatic nucleus of the transgenic hypertensive TGR(mRen2)27 rat and effects on cardiovascular rhythms. Brain Res 2000; 883:250-7. [PMID: 11074056 DOI: 10.1016/s0006-8993(00)02989-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Immediate early genes, especially c-fos, are thought to play an essential role in photic entrainment of circadian rhythms. A special characteristic of the transgenic hypertensive TGR(mRen2)27 rat strain, expressing an additional mouse renin2 gene, is the inverse blood pressure rhythm in relation to those in heart rate and activity resulting in internal desynchronisation of these physiological rhythms. Assessment of c-fos mRNA expression by microdissection and RT-PCR in the suprachiasmatic nucleus showed, that in contrast to normotensive Sprague-Dawley rats the 24 h and circadian rhythm of c-fos mRNA expression in TGR(mRen2)27 rats is abolished. Moreover, light-induced c-fos expression within the nucleus could be found in the normotensive controls, but was absent in transgenic hypertensive rats. The light pulse applied during the subjective night, at CT 14, significantly phase delayed rhythms in blood pressure, heart rate and activity in the normotensive rats by about 2 h, whereas in the transgenic hypertensive animals rhythms in blood pressure and heart rate were unaffected, only activity showed a slight phase shift. In conclusion, these data suggest that the transgene in TGR leads not only to a disturbance of the cardiovascular system but also influences the light entrainment response, which is accompanied by a suppressed c-fos mRNA expression in the suprachiasmatic nucleus.
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Affiliation(s)
- B Lemmer
- Institute of Pharmacology and Toxicology, University of Heidelberg, Maybachstr. 14-16, 68169, Mannheim, Germany.
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