Priming phenomenon, in which an earlier exposure to a stimulus or condition alters synaptic plasticity in response to a subsequent stimulus or condition, known as a challenge, is an example of metaplasticity. In this review, we make the case that the locus coeruleus noradrenergic system-medial perforant path-dentate gyrus pathway is a neural ensemble amenable to studying priming-challenge effec...

Mice carrying mutant amyloid-β precursor protein and presenilin-1 genes (APP/PS1 double transgenic mice) have frequently been used in studies of Alzheimer's disease; however, such studies have focused mainly on hippocampal and cortical changes. The severity of Alzheimer's disease is known to correlate with the amount of amyloid-β protein deposition and the number of dead neurons in the locus co...

BACKGROUND Depression, one of the most frequent psychiatric disturbances in Alzheimer disease (AD), is proposed to have its neurobiological basis in neuron loss in the noradrenergic locus coeruleus, although this is not the case in idiopathic depression. METHODS We performed image analyzer-assisted morphometry of the locus coeruleus in 6 depressed, 6 transiently depressed, and 6 nondepressed ...

We compared in albino and pigmented rats the early effect of unilateral labyrinthectomy (UL) on the concentrations of monoamines (norepinephrine, dopamine, serotonin) and their respective metabolites--3-methoxy,4-hydroxyphenylglycol (MHPG), 3,4-dihydroxy-phenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5HIAA)--in medial vestibular nuclei (MVN), locus coeruleus, raphe dorsalis, and coc...

IMPORTANCE Animal data suggest that chronic stress is associated with a reduction in norepinephrine transporter (NET) availability in the locus coeruleus. However, it is unclear whether such models are relevant to posttraumatic stress disorder (PTSD), which has been linked to noradrenergic dysfunction in humans. OBJECTIVES To use positron emission tomography and the radioligand [11C]methylreb...

The chicken locus coeruleus contains a population of noradrenergic neurons which express the neurotrophin receptor p75 (von Bartheld and Bothwell, 1992). To determine which neurotrophin may regulate the development of noradrenergic neurons in the chicken locus coeruleus, expression of trk receptors, retrograde transport of neurotrophins, and responses to NGF were examined. P75-expressing noradr...

introduction: noradrenergic cells in lc participate in the process of cortical activation and behavioral arousal. the evidence suggests that locus ceoruleus (lc) plays an important role in the sleep-wake cycle. the aim of this study was stereological estimation of cavity caused by lesion and assessment of sleep stages after bilateral lesion of the lc. materials and methods: male wistar rats wei...

introduction: previous studies have shown that stimulation of lateral hypothalamus (lh) produces antinociception. orexin-a (oxa) receptor is strongly expressed in the nucleus locus coeruleus (lc) and orexinergic fibers densely project from lh to lc. in this study, we assessed the role of lc and its oxa receptors in antinociceptive response induced by lh chemical stimulation in the rat. methods:...