We have studied a possible role for cyclic AMP-dependent protein kinase in mediating opiate addiction in the central nervous system by focusing on the rat locus coeruleus. This brain region is well suited for these studies because it is relatively homogeneous and because a wealth of electrophysiological and behavioral data indicate that it plays an important role in mediating the chronic effect...

Hypocretin/orexin neurons give rise to an extensive projection system, portions of which innervate multiple regions associated with the regulation of behavioral state. These regions include the locus coeruleus, medial septal area, medial preoptic area, and substantia innominata. Evidence indicates that hypocretin modulates behavioral state via actions within each of these terminal fields. To un...

We describe a case of a 48-year-old woman who underwent a resection of a tectal pilocytic astrocytoma complicated by a sequence of fluctuating consciousness, psychosis with complex hallucinations and lasting sleeping disturbances in which she vividly acts out her dreams. Based on the clinical and anatomical evidence of this case, we propose the term locus coeruleus syndrome to describe this ass...

Objective(s):The relationship between tramadol, as an antinociceptive drug, and locus coeruleus (LC), the main noradrenergic nucleus of the brain that affects regulation and modulation of pain through descending noradrenergic pathways was investigated. Materials and Methods: Male Sprague-Dawley rats were divided into four groups of 10 rats. The rats were fixed in stereotaxic instrument and then...

An important dimension of cognitive control is the adaptive regulation of the balance between exploitation (pursuing known sources of reward) and exploration (seeking new ones) in response to changes in task utility. Recent studies have suggested that the locus coeruleus-norepinephrine system may play an important role in this function and that pupil diameter can be used to index locus coeruleu...

Glutamatergic activation of the locus coeruleus results in long-term potentiation of dentate gyrus perforant path-evoked population spike amplitude, when paired with perforant path stimulation (.25 Hz). In vitro evidence, however, suggests that this β-adrenoceptor-mediated effect can also occur in the absence of perforant path activity. The present study seeks to determine whether pairing of pe...

GTP cyclohydrolase I is the first and rate-limiting enzyme for the de novo biosynthesis of tetrahydrobiopterin, which is the cofactor for tyrosine hydroxylase. Lipopolysaccharide can modulate tetrahydrobiopterin production by upregulating GTP cyclohydrolase I protein expression in the locus coeruleus in the mouse brain. The increased supply of tetrahydrobiopterin in the locus coeruleus leads to...

Prenatal stress (PS) durably influences responses of rats from birth throughout life by inducing deficits of the hypothalamo-pituitary-adrenal (HPA) axis feedback. The neuronal mechanisms sustaining such alterations are still unknown. The purpose of the present study was to determine whether in PS and control rats, the exposure to a mild stressor differentially induces Fos protein in hippocampu...

Background Insulin-like Growth Factor I (IGF-I) is a peptide involved in many processes the brain. Recently, we described how IGF-I modulates sleep behavior, response to stress, and its role cognition through cholinergic, orexinergic, locus coeruleus nuclei. Nonetheless, modulation of social behavior remains explored, especially during aging Alzheimer’s disease pathology. This study aims determ...