Table 5.
Circadian rhythms in noradrenaline levels.
| Noradrenaline-Circadian Rhythms | |||||
|---|---|---|---|---|---|
| Reference_ID | Animals | L/D Cycle | Duration | Brain Region | Noradrenaline Levels |
| Barbier et al (2007) [55] | Rats | 6h–18h | 20h | Prefrontal Cortex | Higher during DP, stable during LP |
| Dugovic et al (2009) [54] | Rats | 6h–18h | 6h | Prefrontal Cortex | Higher during DP, stable during LP |
| Robinson et al (1991) [57] | Sheep | natural | 20h | Preoptic Area | Decrease gradually |
| Alfinito et al (2009) [58] | Rats | 12:12 | 12h30 | Preoptic Area | Higher during DP, stable during LP |
| Mitome et al (1994) a [37] | Rats | 6h–18h | 52h | Paraventricular Nucleus | Higher during DP, lower during LP |
| Stanley et al (1989) b [98] | Rats | 9h–21h | 48h | Paraventricular Nucleus | Peak 1h after DP onset, followed by sudden decrease, until a second smaller peak at 3h before LP. Lower levels during LP |
| Mitome et al (1994) b [99] | Rats | 6h–18h | 54h | Paraventricular Nucleus | Higher during DP, lower during LP |
| Morien et al (1995) A [100]* | Rats | 7h–19h | 24h | Paraventricular Nucleus | Peak 1h and 8h after DP onset. Higher during DP, lower during LP |
| Smriga et al (2000) b [101] | Rats | 7h–19h | 24h | Lateral Hypothalamus | Gradual increase from baseline during LP Peak at DP onset followed by sudden decrease and return to baseline |
| Smriga et al (2000) a [102] | Rats | 7h–19h | 26h | Ventral Hypothalamus | Higher during DP, lower during LP |
| Kalen et al (1989) [82] | Rats | 12:12 | 24h | Caudal Hippocampus | Higher during DP, lower during LP |
| Drijfhout et al (1996) [103] | Rats | 6h–18h | 16h | Pineal gland | Peak 1–3h after DP onset, decrease 2h before LP Higher during DP, lower during LP |
| Morien et al (1995) B [100]* | Rats | 7h–19h | 24h | Septal Nuclei and the Ventromedial Thalamus | Stable |
Each row represents one study (i.e. an experimental group within a publication) and a qualitative description of the results. Fluctuations are described as “higher” and “lower” disregarding actual magnitudes of changes. Rows are sorted by brain region. Lower case letters indicate separate publications from the same authors in the same year; upper cases letters represent separate groups within publications; numbers represent separate brain regions within animals. *These studies provided average monoamine concentrations pooled for several brain regions.
Abbreviations: L/D Cycle: Light-Dark Cycle; LP: Light Phase; DP: Dark phase.