The nuclei of the locus coeruleus and subcoeruleus were examined in human brains from individuals of 14 to 87 years. Serial counts were performed on every tenth Nissl stained paraffin section of melanin containing cells within the entire length of these nuclei. After 63 years, the neuronal population in these nuclei decreased 40%. This significant decrease in cell number is the first reported f...

Phosphorylation of the μ-opioid receptor (MOR) is known as a key step in desensitization and internalization but the role in the development of long-term tolerance at the cellular level is not known. Viral expression of wild type (exWT) and mutant MORs, where all phosphorylation sites on the C-terminus (Total Phosphorylation Deficient (TPD)) were mutated to alanine, were examined in locus coeru...

Selectively bred rat lines, developed to model genetic contributions to alcohol abuse, include the Indiana alcohol-preferring (P) and alcohol-nonpreferring (NP) lines, and the Alko-Alcohol (AA) and Alko-Nonalcohol (ANA) lines. Preferring and nonpreferring lines were compared in their response to intraperitoneal injection of either ethanol or isotonic saline using c-Fos expression as a marker of...

Cataplexy, a symptom of narcolepsy, is a loss of muscle tone usually triggered by sudden, emotionally significant stimuli. We now report that locus coeruleus neurons cease discharge throughout cataplexy periods in canine narcoleptics. Locus coeruleus discharge rates during cataplexy were as low as or lower than those seen during rapid-eye-movement sleep. Prazosin, an alpha1 antagonist, and phys...

In 22 patients with Alzheimer's disease loss of neurons from the nucleus basalis of Meynert and locus caeruleus averaged 58% and 71% respectively with nucleolar volume being reduced by 30% in both. These changes were greater in those patients under 80 years of age and in such patients damage to the locus was more severe than that to the nucleus basalis. In older patients (over 80 years) changes...

The spatiotemporal dynamics of opioid signaling in the brain remain poorly defined. Photoactivatable opioid ligands provide a means to quantitatively measure these dynamics and their underlying mechanisms in brain tissue. Although activation kinetics can be assessed using caged agonists, deactivation kinetics are obscured by slow clearance of agonist in tissue. To reveal deactivation kinetics o...

The release of the neurotransmitter norepinephrine throughout the mammalian brain is important for modulating attention, arousal, and cognition during many behaviors. Furthermore, disruption of norepinephrine-mediated signaling is strongly associated with several psychiatric and neurodegenerative disorders in humans, emphasizing the clinical importance of this system. Most of the norepinephrine...

The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis) and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a...

Error processing during motor control involves the evaluation of "high-level" errors (i.e., failures to meet a system goal) by a frontal system involving anterior cingulate cortex and the evaluation of "low-level" errors (i.e., discrepancies between actual and desired motor commands) by a posterior system involving posterior parietal cortex. We have recently demonstrated that high-level errors ...

In the present study, the effects of intra-locus coeruleus injection of a dopamine D(1) receptor agonist (SKF38393) on naloxone-induced withdrawal signs of morphine-dependent rats were examined. Twenty different withdrawal signs were assessed. The total withdrawal score was calculated and used as an index of withdrawal intensity for comparison. The D(1) agonist and antagonist were injected 15 a...