Neuroscience letters
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Neuroscience letters · May 2011
Case ReportsTransient alcohol craving suppression by rTMS of dorsal anterior cingulate: an fMRI and LORETA EEG study.
It has recently become clear that alcohol addiction might be related to a brain dysfunction, in which a genetic background and environmental factors shape brain mechanisms involved with alcohol consumption. Craving, a major component determining relapses in alcohol abuse has been linked to abnormal activity in the orbitofrontal cortex, dorsal anterior cingulated cortex (dACC) and amygdala. We report the results of a patient who underwent rTMS targeting the dACC using a double cone coil in an attempt to suppress very severe intractable alcohol craving. ⋯ On fMRI nucleus accumbens, ACC and PCC activation returned to the initial activation pattern. A pathophysiological approach is described to suppress alcohol craving temporarily by rTMS directed at the anterior cingulate. Linking functional imaging changes to craving intensity suggests this approach warrants further exploration.
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Neuroscience letters · May 2011
Comparative StudyContribution of peripheral versus central EP1 prostaglandin receptors to inflammatory pain.
Prostaglandin E(2) (PGE(2)) is a key mediator of exaggerated pain sensation during inflammation. Drugs targeting the PGE(2) pathway by global inhibition of cyclooxygenases are well established in the treatment of inflammatory pain, but also cause significant unwanted effects. Enzymes downstream of the cyclooxygenases, or prostaglandin receptors are candidate targets possibly enabling therapeutic intervention with potentially fewer side effects. ⋯ These results support a major contribution of EP1 receptors to peripheral heat sensitization, but only a minor role in mechanical sensitization and in spinal heat sensitization by PGE(2). After local subcutaneous zymosan A injection, EP1(-/-) mice showed indistinguishable mechanical and heat sensitization compared with wild-type mice. Taken together, these results suggest that peripheral EP1 receptors contribute significantly to inflammation induced heat pain sensitization while evidence for a contribution to central sensitization was not obtained.
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Neuroscience letters · May 2011
Comparative StudyHippocampal atrophy rates in Alzheimer's disease: automated segmentation variability analysis.
Hippocampal (HC) atrophy and atrophy rates are putative clinical markers of progression to Alzheimer's disease (AD). We compared results given by two different automated HC segmentation techniques in the Alzheimer's Disease Neuroimaging Initiative dataset between two time intervals. We used HC volumetric automated segmentation data for a total of 683 patients at baseline (198 controls, 331 with mild cognitive impairment (MCI) and 154 with AD), 684 at 6 months (198 controls, 332 with MCI and 154 with AD) and 587 at 12 months (176 controls, 280 with MCI and 131 with AD). ⋯ When compared to mean rates from largely manual segmentation, automated segmentation results show increased atrophy rates for both SNT and FreeSurfer techniques. While sensitive, there remains substantial technique variability, likely due to differences in methodological approaches and especially neuroanatomical HC definitions. These fundamental metrological problems need to be resolved before concluding with certainty on the accuracy and reliability of automated techniques.
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Neuroscience letters · May 2011
Receptors involved in the antinociception of intrathecal melatonin in formalin test of rats.
The authors examined the antinociceptive effect of melatonin in a nociceptive state and investigated a possible interaction with adrenergic or cholinergic receptors underlying this effect at the spinal level. Nociception was induced by a subcutaneous injection of 50 μl of a 5% formalin solution to the hindpaw of male Sprague-Dawley rats. The reversal effects of alpha-1 adrenoceptor antagonist (prazosin), alpha-2 adrenoceptor antagonist (yohimbine), muscarinic receptor antagonist (atropine) and nicotinic receptor antagonist (mecamylamine) on the activity of melatonin were assessed. ⋯ Intrathecal prazosin, yohimbine, atropine and mecamylamine increased the attenuating flinching response in both phases observed by intrathecal melatonin. Collectively, the present data suggest that intrathecal melatonin attenuates the facilitated state and acute pain evoked by formalin injection. Furthermore, the antinociception of melatonin is mediated through the alpha-1 adrenoceptor, alpha-2 adrenoceptor, muscarinic and nicotinic receptors in the spinal cord.