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. 2008 Sep;6(3):235-53.
doi: 10.2174/157015908785777229.

Functional neuroanatomy of the noradrenergic locus coeruleus: its roles in the regulation of arousal and autonomic function part I: principles of functional organisation

E R Samuels  1 , E Szabadi
Affiliations

Functional neuroanatomy of the noradrenergic locus coeruleus: its roles in the regulation of arousal and autonomic function part I: principles of functional organisation

E R Samuels et al. Curr Neuropharmacol. 2008 Sep.

Abstract

The locus coeruleus (LC) is the major noradrenergic nucleus of the brain, giving rise to fibres innervating extensive areas throughout the neuraxis. Recent advances in neuroscience have resulted in the unravelling of the neuronal circuits controlling a number of physiological functions in which the LC plays a central role. Two such functions are the regulation of arousal and autonomic activity, which are inseparably linked largely via the involvement of the LC. The LC is a major wakefulness-promoting nucleus, resulting from dense excitatory projections to the majority of the cerebral cortex, cholinergic neurones of the basal forebrain, cortically-projecting neurones of the thalamus, serotoninergic neurones of the dorsal raphe and cholinergic neurones of the pedunculopontine and laterodorsal tegmental nucleus, and substantial inhibitory projections to sleep-promoting GABAergic neurones of the basal forebrain and ventrolateral preoptic area. Activation of the LC thus results in the enhancement of alertness through the innervation of these varied nuclei. The importance of the LC in controlling autonomic function results from both direct projections to the spinal cord and projections to autonomic nuclei including the dorsal motor nucleus of the vagus, the nucleus ambiguus, the rostroventrolateral medulla, the Edinger-Westphal nucleus, the caudal raphe, the salivatory nuclei, the paraventricular nucleus, and the amygdala. LC activation produces an increase in sympathetic activity and a decrease in parasympathetic activity via these projections. Alterations in LC activity therefore result in complex patterns of neuronal activity throughout the brain, observed as changes in measures of arousal and autonomic function.

Keywords: Locus coeruleus; arousal; autonomic function; autoreceptors.; brainstem; diencephalons; forebrain; spinal cord.

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References

    1. Abduljawad KAJ, Langley RW, Bradshaw CM, Szabadi E. Effects of clonidine and diazepam on the acoustic startle response and on its inhibition by ‘prepulses’ in man. J. Psychopharmacol. 1997;11:29–34. - PubMed
    1. Abduljawad KAJ, Langley RW, Bradshaw CM, Szabadi E. Effects of clonidine and diazepam on prepulse inhibition of the acoustic startle response and the N1/P2 auditory evoked potential in man. J. Psychopharmacol. 2001;15:237–242. - PubMed
    1. Acosta-Martinez M, Fiber JM, Brown RD, Etgen AM. Localization of α1B-adrenergic receptor in female rat brain regions involved in stress and neuroendocrine function. Neurochem. Int. 1999;35:383–391. - PubMed
    1. Aghajanian GK, Cedarbaum JM, Wang RY. Evidence for norepinephrine-mediated collateral inhibition of locus coeruleus neurons. Brain Res. 1977;136:570–577. - PubMed
    1. Aghajanian GK, Wang YY. Common alpha-1 and opiate effector mechanisms in the locus coeruleus intracellular studies in brain slices. Neuropharmacology. 1987;26:793–799. - PubMed

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