Neuroscience letters
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Neuroscience letters · Apr 2011
Comparative StudyHippocampal-dependent antidepressant-like activity of histone deacetylase inhibition.
Chronic social defeat stress in mice significantly decreases subsequent social interactions and induces other depression-like behaviors. Here we measured and manipulated levels of acetylated histone H3 (acH3), a chromatin mark of transcriptional activation, in the hippocampus and amygdala after ten continuous days of social defeat stress in male C57/Bl6J mice. This form of social stress causes a transient increase, followed by a persistent decrease, in the levels of acH3 in hippocampus. ⋯ However, when HDAC inhibitors are infused into hippocampus during social housing with another male, social avoidance is attenuated. Interestingly, social avoidance is reversed when MS-275 is infused directly into amygdala. Together, these findings further support the antidepressant potential of HDAC inhibitors, and indicate that temporally overlapping environmental and molecular events are required to optimally reverse specific stress-induced behavioral symptoms.
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Neuroscience letters · Apr 2011
Comparative StudyCurcumin reverses corticosterone-induced depressive-like behavior and decrease in brain BDNF levels in rats.
A rat model of depression has been recently developed using exogenous corticosterone (CORT) administration. This study aimed to examine the antidepressant-like effect and the possible mechanisms of curcumin in a CORT-induced depression model in rats. ⋯ Treatment of the rats with curcumin significantly suppressed the depression-like behavior and the decrease in brain BDNF levels induced by the repeated CORT injections. The results suggest that curcumin produces an antidepressant-like effect in CORT-treated rats, which is possibly mediated by increasing BDNF expression in the hippocampus and frontal cortex.
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Neuroscience letters · Apr 2011
Comparative StudyAntinociceptive effect of intrathecal cannabinoid receptor agonist WIN 55,212-2 in a rat bone tumor pain model.
Bone tumor pain is a poorly controlled pain comprising background and severe pain on moving or weight-bearing postures that decreases the quality of life for cancer patients; thus, more effective analgesics are clearly needed. This study evaluated the efficacy of a cannabinoid (CB) receptor agonist (WIN 55,212-2) on bone tumor pain in the spinal cords of rats, and clarified the roles of the CB1 and CB2 receptors in WIN 55,212-2-induced antinociception at the spinal level. Bone tumor pain was induced by injecting MRMT-1 tumor cells (1×10(5)) into the right tibias of female Sprague-Dawley rats under sevoflurane anesthesia. ⋯ The antinociceptive effect of WIN 55,212-2 was reversed by both CB1 and CB2 receptor antagonists. Intrathecal WIN 55,212-2 reduced bone tumor-related pain behavior mediated via spinal CB1 and CB2 receptors. Therefore, spinal CB receptor agonists may be novel analgesics in the treatment of bone tumor pain.
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Neuroscience letters · Apr 2011
Comparative StudyNeural correlates of near-misses effect in gambling.
The present study investigated the cognitive and neural mechanisms underlying the gambling near-miss effect by measuring event-related-potentials. Using a simple gambling task, we measured behavioral response and electrophysiological activity of gambling outcomes. ⋯ Dipole source analysis of the difference wave (near-miss minus full-miss) indicated that two generators of the P300, localized in the putamen and orbitofrontal cortex, might be involved in motivational evaluation and regret, respectively. Our findings indicated that the near-miss effect stems from sources: higher levels of motivation and the presence of regret, caused by counterfactual thinking.
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Neuroscience letters · Apr 2011
Comparative StudyP2RX7 polymorphisms Gln460Arg and His155Tyr are not associated with major depressive disorder or remission after SSRI or ECT.
Purinergic receptor P2X, ligand-gated ion channel, 7 (P2RX7) gene polymorphism, has been suggested to be associated with major depressive disorder (MDD). The association between P2RX7 gene polymorphism and remission after serotonin selective reuptake inhibitors (SSRI) or electroconvulsive therapy (ECT) has not previously been studied. The aims of the present study were to test for an association between P2RX7 polymorphisms Gln460Arg (rs2230912) and His155Tyr (rs208294) and MDD in two patient populations compared to controls. ⋯ There were no differences in allele or genotype frequencies of either rs2230912 or rs208294 between patient groups and controls. Neither rs2230912 nor rs208294 was associated with MDD or remission after SSRI or ECT. The results suggest that P2RX7 gene polymorphisms Gln460Arg (rs2230912) and His155Tyr (rs208294) are not associated with MDD or remission after SSRI or ECT.