{
"papers": [
{
"n": 8,
"doi": "10.1126/sciadv.adq0651",
"value": "10 ± 5 s",
"study_system": "mouse",
"value_source_sentence": "to 12:30 p.m.), laser stimulation (10 mW, 532 or 589 nm, 10-ms pulses at 10 Hz or a 2-s pulse every 10 ± 5 s) was applied in 2-min episodes, repeated every 10 min, and sleep-wake states were classified based on electroencephalogram (EEG) and electromyogram (EMG) recordings ( Fig."
},
{
"n": null,
"doi": "10.1101/lm.037283.114",
"value": "firing rates (∼1–3 Hz",
"study_system": "rat",
"value_source_sentence": "Noradrenaline neurons in LC have traditionally been characterized as having low baseline firing rates (∼1–3 Hz) which is modulated by wakefulness (see Berridge and Waterhouse 2003 ; Aston-Jones and Cohen 2005 ; Sara and Bouret 2012 for reviews of basic response properties of LC neurons)."
},
{
"n": null,
"doi": "10.1523/jneurosci.4835-13.2014",
"value": "p < 0.0001",
"study_system": "rat",
"value_source_sentence": "Subsequent optoactivation of the LC evoked repeatable, robust, antinociceptive (+4.7°C ± 1.0, p < 0.0001) or pronociceptive (-4.4°C ± 0.7, p < 0.0001) changes in hindpaw thermal withdrawal thresholds."
},
{
"n": null,
"doi": "10.1101/2022.09.07.506929",
"value": "see source",
"study_system": "rat",
"value_source_sentence": "Selective chemogenetic-activation of subsets of LC neurons (expressing the ionotropic actuator PSAM) revealed both a direct excitation (after application of PSEM308, 3-30µM) and an α2R-mediated inhibition of neighbouring LC cells (non-transduced)."
},
{
"n": null,
"doi": "10.1016/j.nbd.2023.106355",
"value": "55%",
"study_system": "rat",
"value_source_sentence": "The seizure-induced change in firing rate differed between LC neurons: 55% of neurons decreased in firing rate during seizures, while 28% increased their firing rate."
},
{
"n": 6,
"doi": "10.1093/texcom/tgab026",
"value": "firing rate averaged ~ 18 Hz",
"study_system": "rat",
"value_source_sentence": "Within burst firing rate averaged ~ 18 Hz with overall firing at 2 Hz."
},
{
"n": null,
"doi": "10.1523/jneurosci.0454-15.2015",
"value": "see source",
"study_system": "non-human primate",
"value_source_sentence": "Conversely, the firing of noradrenergic neurons increased with both pupil dilation and effort production in relation to the energization of behavior."
},
{
"n": 12,
"doi": "10.1523/jneurosci.2408-24.2025",
"value": "robust decrease",
"study_system": "rat",
"value_source_sentence": "Stimulation parameters were chosen based on a previous in vitro electrophysiological study conducted in acute brain slices demonstrating that laser stimulation using the abovementioned parameters resulted in a robust decrease in resting membrane potential ( Banks et al., 2021 )."
},
{
"n": null,
"doi": "10.1186/s40478-017-0411-2",
"value": "30%",
"study_system": "rat",
"value_source_sentence": "Stereologic estimates of total LC neuron number revealed a 30% loss during the transition from NCI to aMCI, with an additional 25% loss of LC neurons in AD."
},
{
"n": null,
"doi": "10.1038/s41583-020-0360-9",
"value": "firing rates in the range of 0.5–5 Hz",
"study_system": "non-human primate",
"value_source_sentence": "LC neurons ex vivo, recorded almost exclusively from very young brains, display spontaneous firing rates in the range of 0.5–5 Hz 72 , 76 ."
},
{
"n": null,
"doi": "10.1016/j.neuroscience.2024.07.032",
"value": "see source",
"study_system": "rat",
"value_source_sentence": "Additionally, our specific activation of the LC noradrenergic neurons showed effective behavioral readout using chemogenetics of this rat line."
},
{
"n": 7,
"doi": "10.1126/sciadv.adw6375",
"value": "P = 0.004",
"study_system": "mouse",
"value_source_sentence": "We found a statistically significant difference in the anatomical distribution of BF-projecting versus PRN-projecting LC neurons ( P = 0.004, Monte Carlo permutation test), implying that the BF and PRN neuronal projections of the LC are different subpopulations."
},
{
"n": null,
"doi": "10.3389/fnbeh.2012.00020",
"value": "4.3%",
"study_system": "rat",
"value_source_sentence": "In LC, however, only 4.3% of retrogradely labeled neurons possessed collaterals targeting any two prefrontal subregions simultaneously, and no cells were identified that projected to all three regions."
},
{
"n": null,
"doi": "10.1186/s12974-023-02865-z",
"value": "significantly more",
"study_system": "mouse",
"value_source_sentence": "Interestingly, EAE-rM3D onset mice spent significantly more time in the center of the field in the chronic phase (25 dpi: p < 0.05; Fig."
},
{
"n": null,
"doi": "10.1016/j.tins.2018.10.002",
"value": "see source",
"study_system": "rat",
"value_source_sentence": "While axons from the ventral tegmental area (VTA) were generally thought to be the exclusive source of hippocampal dopamine, recent studies have demonstrated that noradrenergic neurons in the locus coeruleus (LC) corelease noradrenaline and dopamine in the hippocampus and that their dopamine release boosts memory retention as well."
}
],
"x_axis": "Species",
"y_axis": "LC neuron count",
"n_analyzed": "varies by study",
"description": "Comparison of LC neuron numbers across species to illustrate the global broadcast paradox",
"figure_type": "bar_chart_with_scale_annotations",
"n_definition": "stereological neuron counts from histological studies",
"scope_region": "locus coeruleus",
"comparison_type": "LC neuron count and projection density across species",
"taxonomic_level": "species",
"scope_population": "noradrenergic neurons in LC",
"homogeneity_check": {
"caveats": [
"Different counting methods (stereological vs non-stereological)",
"Fixation protocols affect apparent neuron numbers",
"Age effects not always controlled",
"LC boundary definitions vary across labs"
],
"comparable": true
}
}