Daily Rhythms of Fos Expression in Hypothalamic Targets of the Suprachiasmatic Nucleus in Diurnal and Nocturnal Rodents

Núñez, Antonio A.; Bult, Abel; McElhinny, Teresa L.; Smale, Laura

doi:10.1177/074873099129000713

Cited by 66 publications

(61 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This area corresponds to the dorsal extension of the RHT terminal plexus from the SCN into the subparaventricular region and more caudal hypothalamus (Muscat et al, 2003). The light flash or pulse-induced FOS in the subparaventricular region is consistent with results from rat and grass rat (Nunez et al, 1999).…”

Section: Light-induced Fos Protein Expressionsupporting

confidence: 83%

Absence of Normal Photic Integration in the Circadian Visual System: Response to Millisecond Light Flashes

Vidal

Morin²

2007

J. Neurosci.

View full text Add to dashboard Cite

Light is the most prominent synchronizing stimulus for circadian rhythms. The circadian visual system responds in accordance with the energy content of photic stimuli longer than a few seconds. Here, as few as three flashes (2 ms each delivered to hamsters over 5 or 60 min at circadian time 19) elicited large phase advances. Ten or more flashes were required to induce FOS protein in the suprachiasmatic nucleus (SCN), and such induction occurred throughout the entire SCN, as well as outside the nucleus. High-density flash stimulation (0.5 s interflash interval) was ineffective, but response increased as the interval increased up to 4 s. In an irradiance response test, phase shifts appeared to be all-or-none with threshold irradiance between 140 and 1070 W/cm 2 , implying lack of stimulus energy summation. Nevertheless, an irradiance ineffective when delivered as 10 flashes induced phase shifts when given as100 flashes, but the response was substantially smaller than elicited by 10 flashes, each with ϳ1 log unit more irradiance. The results also show reduced sensitivity of flash-induced FOS response in the intergeniculate leaflet compared with the SCN, contrary to studies using longer light stimuli. Masking was robust and prolonged in response to 10 flashes. The data demonstrate that the circadian visual system responds markedly to brief, intense light stimuli without normal photic integration. This may involve a second input pathway different from that mediating the effects of longer, dimmer photic stimuli.

show abstract

Section: Light-induced Fos Protein Expressionsupporting

confidence: 83%

Absence of Normal Photic Integration in the Circadian Visual System: Response to Millisecond Light Flashes

Vidal

Morin²

2007

J. Neurosci.

View full text Add to dashboard Cite

show abstract

“…It is thus well positioned to integrate direct photic signals from the retina with circadian signals, and to modulate the same functions that are regulated by the SCN. There is some evidence that the vSPZ may contribute to diurnality of the grass rat circadian system, as it exhibits rhythms in cFOS that are very different from those seen in nocturnal lab rats [108] and that persist in DD [66]. Lesions in this area also lead to a reduction in the ratio of activity during subjective day relative to night in these animals and to a decrease in the rate of reentrainment following a shift in the LD cycle [109].…”

Section: Discussionmentioning

confidence: 99%

Acute effects of light on the brain and behavior of diurnal Arvicanthis niloticus and nocturnal Mus musculus

Shuboni

Cramm

Yan

et al. 2015

Physiology & Behavior

Self Cite

View full text Add to dashboard Cite

Photic cues influence daily patterns of activity via two complementary mechanisms: (1) entraining the internal circadian clock and (2) directly increasing or decreasing activity, a phenomenon referred to as “masking”. The direction of this masking response is dependent on the temporal niche an organism occupies, as nocturnal animals often decrease activity when exposed to light, while the opposite response is more likely to be seen in diurnal animals. Little is known about the neural mechanisms underlying these differences. Here, we examined the masking effects of light on behavior and the activation of several brain regions by that light, in diurnal Arvicanthis niloticus (Nile grass rats) and nocturnal Mus musculus (mice). Each species displayed the expected behavioral response to a 1 h pulse of light presented 2 h after lights-off, with the diurnal grass rats and nocturnal mice increasing and decreasing their activity, respectively. In grass rats light induced an increase in cFOS in all retinorecipient areas examined, which included the suprachiasmatic nucleus (SCN), the ventral subparaventricular zone (vSPZ), intergeniculate leaflet (IGL), lateral habenula (LH), olivary pretectal nucleus (OPT) and the dorsal lateral geniculate (DLG). In mice, light led to an increase in cFOS in one of these regions (SCN), no change in others (vSPZ, IGL and LH) and a decrease in two (OPT and DLG). In addition, light increased cFOS expression in three arousal-related brain regions (the lateral hypothalamus, dorsal raphe, and locus coeruleus) and in one sleep-promoting region (the ventrolateral preoptic area) in grass rats. In mice, light had no effect on cFOS in these four regions. Taken together, these results highlight several brain regions whose responses to light suggest that they may play a role in masking, and that the possibility that they contribute to species-specific patterns of behavioral responses to light should be explored in future.

show abstract

“…These differences have been identified through the examination of Fos in the brains of the unstriped Nile grass rat ( Arvicanthis niloticus ), a diurnal rodent from East Africa. In males of this species, Fos is expressed rhythmically in the lower sub-paraventricular zone (LSPV) immediately dorsal to the SCN with a pattern quite different from that seen in nocturnal laboratory rats, and in constant darkness these rhythms persist in the former, but not the latter, species (Nunez et al, 1999; Schwartz et al, 2004). PER1 rhythms are also apparent in the LSPV of male grass rats kept in either LD (Ramanathan et al, 2006) or constant dark conditions (C. Ramanathan et al, unpublished observations).…”

mentioning

confidence: 84%

Daily rhythms in PER1 within and beyond the suprachiasmatic nucleus of female grass rats (Arvicanthis niloticus)

2008

View full text Add to dashboard Cite

Although circadian rhythms of males and females are different in a variety of ways in many species, their mechanisms have been primarily studied in males. Furthermore, rhythms are dramatically different in diurnal and nocturnal animals but have been studied predominantly in nocturnal ones. In the present study, we examined rhythms in one element of the circadian oscillator, the PER1 protein, in a variety of cell populations in brains of diurnal female grass rats. Every 4 h five adult female grass rats kept on a 12-h light/dark (LD) cycle were perfused and their brains were processed for immunohistochemical detection of PER1. Numbers of PER1-labeled cells were rhythmic not only within the suprachiasmatic nucleus (SCN), the locus of the primary circadian clock in mammals, but also in the peri-suprachiasmatic region, the oval nucleus of the bed nucleus of the stria terminalis, the central amygdala, and the nucleus accumbens. In addition, rhythms were detected within populations of neuroendocrine cells that contain tyrosine hydroxylase. The phase of the rhythm within the SCN was advanced compared with that seen previously in male grass rats. Rhythms beyond the SCN were varied and different from those seen in most nocturnal species, suggesting that signals originating in the SCN are modified by its direct and/or indirect targets in different ways in nocturnal and diurnal species.

show abstract

Daily Rhythms of Fos Expression in Hypothalamic Targets of the Suprachiasmatic Nucleus in Diurnal and Nocturnal Rodents

Cited by 66 publications

References 26 publications

Absence of Normal Photic Integration in the Circadian Visual System: Response to Millisecond Light Flashes

Absence of Normal Photic Integration in the Circadian Visual System: Response to Millisecond Light Flashes

Acute effects of light on the brain and behavior of diurnal Arvicanthis niloticus and nocturnal Mus musculus

Daily rhythms in PER1 within and beyond the suprachiasmatic nucleus of female grass rats (Arvicanthis niloticus)

Contact Info

Product

Resources

About