“Although a considerable number of patients suffer from co


“Although a considerable number of patients suffer from cognitive impairments after stroke, the neural mechanism of cognitive recovery has not yet been clarified. Repeated resting-state functional magnetic resonance imaging (fMRI) was used in this study to examine longitudinal changes in the default-mode network (DMN) during the 6 months after stroke, and to investigate the relationship between DMN changes and cognitive recovery. Out of 24 initially recruited right-hemispheric stroke patients, 11 (eight males, mean age 55.7 years) successfully completed the repeated fMRI protocol.

Patients selleck inhibitor underwent three fMRI sessions at 1, 3 and 6 months after stroke. Their DMNs were analysed and compared with those of 11 age-matched healthy subjects (nine males, mean age 56.2 years). Correlations between DMN connectivity and improvement of the cognitive performance scores were also assessed. The stroke patients were found to demonstrate markedly decreased DMN connectivity of the posterior cingulate cortex, precuneus,

Natural Product Library order medial frontal gyrus and inferior parietal lobes at 1 month after stroke. At 3 months after stroke, the DMN connectivity of these brain areas was almost restored, suggesting that the period is critical for neural reorganization. The DMN connectivity of the dorsolateral prefrontal cortex in the contralesional hemisphere showed a significant correlation with cognitive function recovery in stroke patients, and should be considered a compensatory process for overcoming cognitive Cediranib (AZD2171) impairment due to brain lesion. This is the first longitudinal study to demonstrate the changes in DMN during recovery after stroke and the key

regions influencing cognitive recovery. “
“Corticotropin-releasing factor (CRF) in the amygdala is involved in stress responses. Moreover, dopaminergic neurotransmission in the brain reward system including the amygdala plays a significant role in the pathology of cocaine addiction. The present study analysed CRF-induced synaptic plasticity, its pharmacological sensitivity and interactions with the dopamine (DA) system in the basolateral to lateral capsula central amygdala (lcCeA) pathway after a 2-week withdrawal from repeated cocaine administration. A physiologically relevant CRF concentration (25 nm) induced long-term potentiation (LTP) that was enhanced after cocaine withdrawal. In saline-treated rats, CRF-induced LTP was mediated through N-methyl-d-aspartate (NMDA) receptors, L-type voltage-gated calcium channels (L-VGCCs) and CRF1 receptors. However, in cocaine-withdrawn animals, activation of CRF1 and CRF2 receptors was found to enhance LTP. This enhanced CRF-induced LTP after cocaine withdrawal was mediated through endogenous activation of both D1- and D2-like receptors. Furthermore, expression of the D1 receptor (D1R) but not the D2R, D3R, D4R or D5R was significantly increased after cocaine withdrawal.

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