Neuroscience
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Peripherally restricted analgesics are desirable to avoid central nervous system (CNS) side effects of opioids. Nonsteroidal anti-inflammatory drugs produce peripheral analgesia but have significant toxicity. GABA(B) receptors represent peripheral targets for analgesia but selective GABA(B) agonists like baclofen cross the blood-brain barrier. ⋯ In a mouse model of osteoarthritis, isovaline restored performance during forced exercise to baseline values. Immunohistochemical staining of cutaneous layers of the analgesic test site demonstrated co-localization of GABA(B1) and GABA(B2) receptor subunits on fine nerve endings and keratinocytes. Isovaline represents a new class of peripherally restricted analgesics without CNS effects, mediated by cutaneous GABA(B) receptors.
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During exercise, intense brain activity orchestrates an increase in muscle tension. Additionally, there is an increase in cardiac output and ventilation to compensate the increased metabolic demand of muscle activity and to facilitate the removal of CO(2) from and the delivery of O(2) to tissues. Here we tested the hypothesis that a subset of pontomedullary and hypothalamic neurons could be activated during dynamic acute exercise. ⋯ In summary, we show for the first time that after acute exercise there is an intense activation of brain areas crucial for cardiorespiratory control. Possible involvement of the central command mechanism should be considered. Our results suggest whole brain-specific mobilization to correct and compensate the homeostatic changes produced by acute exercise.
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Gamma-amino butyric acid (GABA)ergic cells play an important inhibitory role in epilepsy. Until now, there are no reports on promoting transplanted bone marrow stromal cells (BMSCs) to differentiate into GABAergic cells for treatment of epilepsy. In this study, hairy and enhancer of split 1 (Hes1)-down regulated BMSCs (H-BMSCs) were transplanted into an epileptic rat model to induce GABAergic cells differentiation to improve the function recovery and neuronal regeneration. ⋯ The results showed that the rate of mortality, frequency of spontaneous recurrent seizures (SRS) and incidence of epileptiform waves presented a tendency to decrease after H-BMSCs transplantation. The histology results showed that (1) the transplanted H-BMSCs which migrated to the adjacent parahippocampal cortical areas expressed glutamate decarboxylase (GAD) 67, neuron-specific enolase (NSE) and some glial fibrillary acidic protein (GFAP), and (2) the neuronal density of corresponding cortical areas was significantly increased (P<0.01 VS. experimental group I or positive control group). Given these results and other advantages of BMSCs, such as easy harvest and minimal immunogenicity, transplantation of H-BMSCs could be a promising approach to improve the functional recovery and neuronal regeneration of epileptic model in the early stage.
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Comparative Study
Sex differences in social interaction behaviors in rats are mediated by extracellular signal-regulated kinase 2 expression in the medial prefrontal cortex.
Considerable sex differences occur in the incidence and prevalence of anxiety disorders where women are more anxious than men, particularly in situations where social interaction is required. In preclinical studies, the social interaction test represents a valid animal model to study sex differences in social anxiety. ⋯ Indeed, female rats' had lower ERK2 expression compared to male rats, and overexpression of ERK2 in the mPFC increases their social interaction to the level seen in their male counterparts. These data indicate that the sexually dimorphic expression of ERK2 mediates social anxiety-like behaviors.
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Meta Analysis
The human vestibular cortex revealed by coordinate-based activation likelihood estimation meta-analysis.
The vestibular system contributes to the control of posture and eye movements and is also involved in various cognitive functions including spatial navigation and memory. These functions are subtended by projections to a vestibular cortex, whose exact location in the human brain is still a matter of debate (Lopez and Blanke, 2011). The vestibular cortex can be defined as the network of all cortical areas receiving inputs from the vestibular system, including areas where vestibular signals influence the processing of other sensory (e.g. somatosensory and visual) and motor signals. ⋯ The only area of convergence between all three methods of stimulation was located in Ri. The data indicate that Ri, parietal operculum and posterior insula are vestibular regions where afferents converge from otoliths and semicircular canals, and may thus be involved in the processing of signals informing about body rotations, translations and tilts. Results from the meta-analysis are in agreement with electrophysiological recordings in monkeys showing main vestibular projections in the transitional zone between Ri, the insular granular field (Ig), and SII.