Neuroscience
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Infancy is a critical period for brain development. Emerging evidence indicates that stress experienced during that period can have long-term programming effects on the brain and behavior. However, whether different time periods represent different vulnerabilities to the programming of different neurobehavioral domains is not yet known. ⋯ ELS-early-treated animals exhibited an increase in nectin-1 expression in the dorsal hippocampus, and this increase was associated with the social deficits seen in these animals. Our findings highlight the relevance of developmental age on stress-induced long-term behavioral alterations. They also suggest potential links between early stress-induced alterations in hippocampal Gabrg2 expression and the developmental programming of anxiety and between changes in hippocampal nectin-1 expression and stress-induced social impairments.
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NMDA receptors (NMDARs) are glutamate-gated ion channels widely expressed in the central nervous system (CNS) and endowed with unique biophysical, pharmacological and signaling properties. These receptors are best known for their critical roles in synaptic plasticity and their implications in a variety of neurological and psychiatric disorders. Since their discovery three decades ago, NMDARs have been thoroughly studied as components of postsynaptic excitatory potentials. ⋯ Contentious issues that animate the field are also discussed. Finally, particular emphasis is put on the molecular and cellular diversity of preNMDARs which translates into a variety of effects, both short- and long-term, on synaptic efficacy. Overshadowed by their postsynaptic counterparts, preNMDARs are progressively emerging as important regulators of neuronal signaling.
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Carbon monoxide (CO), like other gaseous neuromodulators, has a dual nature as both a toxic gas and a physiologically relevant signaling molecule. In the nervous system, high concentrations of CO can lead to neuronal injury while lower concentrations are found to be neuroprotective. The number of cellular targets affected by physiological concentrations of CO is rapidly growing and includes ion channels in various cell types. ⋯ This effect was mediated by the inhibition of voltage-gated calcium channels by CO. The general findings of CO acting as a hyperpolarizing signal and an inhibitor of neuronal excitability extended to B19 neurons. Taken together, these findings suggest that CO is a potent modulator of ion channels with broad implications for the modulation of neural activity in a wide range of neuron-types.
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Ischemic injuries within the motor cortex result in functional deficits that may profoundly impact activities of daily living in patients. Current rehabilitation protocols achieve only limited recovery of motor abilities. The brain reorganizes spontaneously after injury, and it is believed that appropriately boosting these neuroplastic processes may restore function via recruitment of spared areas and pathways. ⋯ I also consider the effects of physical rehabilitation, including robot-assisted therapy, and the potential mechanisms by which motor training induces recovery. Finally, I describe experimental approaches in which training is coupled with delivery of plasticizing drugs that render the remaining, undamaged pathways more sensitive to experience-dependent modifications. These combinatorial strategies hold promise for the definition of more effective rehabilitation paradigms that can be translated into clinical practice.
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The present study was to investigate whether baicalin can prevent repeated exogenous corticosterone injection-induced depressive-like behaviors and explore its possible mechanisms. After a 21-day treatment with baicalin (10 and 20 mg/kg), sucrose preference in the sucrose preference test (SPT) and immobility time in forced swimming test (FST) were observed, serum corticosterone levels and brain-derived neurotrophic factor (BDNF) contents in the hippocampus were examined by enzyme-linked immunosorbent assay (ELISA). In addition, quantitative real-time polymerase chain reaction (qPCR) and western blot were used to detect the mRNA and protein expression in the hippocampus. ⋯ Additionally, baicalin up-regulated the mRNA and protein expression of glucocorticoid receptor (GR) and BDNF, accompanied with the down-regulation of serum- and glucocorticoid-regulated kinase 1 (SGK1) in the hippocampus. Moreover, baicalin significantly increased the protein expression of 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2) in the hippocampus. The present results confirmed the antidepressant-like effects of baicalin in a mice model of depression induced by corticosterone and suggested that its mechanism was possibly involved in reducing serum corticosterone and thereby increasing BDNF in the hippocampus.