Neuroscience
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The subplate (SP) plays important roles in developmental and functional events in the neocortex, such as thalamocortical and corticofugal projection, cortical oscillation generation and corticocortical connectivity. Although accumulated evidence indicates that SP interneurons are crucial for SP function, the molecular composition of SP interneurons as well as their developmental profile and distribution remain largely unclear. In this study, we systematically investigated dynamic development of SP thickness and chemical marker expression in SP interneurons in distinct cortical regions during the first postnatal month. ⋯ Moreover, distinct interneuron subtypes show characteristic temporal and spatial distribution in the SP. nNOS(+) interneurons in the SP increase from the anterior motor cortex to posterior visual cortex, while CR(+) and CB(+) interneurons the opposite. Interestedly, the majority of GABAARδ(+) neurons in SP are non-GABAergic neurons in contrast to other cortical layers. These findings clarify and extend our understanding of SP interneurons in the developing cerebral cortex and will underpin further study of SP function.
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Depression is a common neuropsychiatric disorder which has been associated with a wide range of structural and functional changes within specific brain regions. Ginsenoside Rg1 has been shown to exert a number of neuroprotective effects as demonstrated in various in vivo and in vitro studies. However, little information is available regarding the site and mechanisms of ginsenoside Rg1 in promoting antidepressant effects. ⋯ Taken together, the results of the present study demonstrate that ginsenoside Rg1 exhibits antidepressant-like effects against CUMS-induced depression. This amelioration of depression-like behaviors by ginsenoside Rg1 appears to be mediated, at least in part, by a CREB-regulated increase of BDNF expression in the amygdala of rats. Therefore, these findings reveal the therapeutic potential of ginsenoside Rg1 for use in clinical trials in the treatment of depression.
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Previous studies in our laboratory showed that the organization and heterogeneous molecular composition of extracellular matrix is associated with the variable cytoarchitecture, connections and specific functions of the vestibular nuclei and two related areas of the vestibular neural circuits, the inferior olive and prepositus hypoglossi nucleus. The aim of the present study is to reveal the organization and distribution of various molecular components of extracellular matrix in the red nucleus, a midbrain premotor center. Morphologically and functionally the red nucleus is comprised of the magno- and parvocellular parts, with overlapping neuronal population. ⋯ The most characteristic finding was that the appearance of perineuronal nets was related with the neuronal size independently from its position within the two subdivisions of red nucleus. In line with these statements none of the extracellular matrix molecules were restricted exclusively to the magno- or parvocellular division. The chemical heterogeneity of the perineuronal nets may support the recently accepted view that the red nucleus comprises more different populations of neurons than previously reported.
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The activity of the deep cerebellar nuclei (DCN) neurons conveys the bulk of the output of the cerebellum. To generate these motor signals, DCN neurons integrate synaptic inputs with their own spontaneous activity. We have previously reported that N-type voltage-gated Ca(2+) channels modulate the spontaneous activity of the majority of juvenile DCN neurons in vitro. ⋯ When cadmium was injected into the DCN in vivo no significant change in firing rate was observed, conversely to most juvenile DCN neurons which showed high-frequency bursts after cadmium injection. In these same animals, PCs pacemaking showed no developmental difference. Thus our results demonstrate a remarkable age-dependent functional modification in the regulation of DCN neurons pacemaking.
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Extracts of Asparagus cochinchinensis (AC) have antitumor, anti-inflammatory, and immunostimulant effects. The neurobiological mechanisms underlying the effects of AC have not been sufficiently explored. Thus we performed in vivo and in vitro experiments to further characterize potential therapeutic effects and to clarify the underlying mechanisms. ⋯ Moreover, AC-induced activation of pShp-2 and ErK1/2 were blocked by NSC87877 indicating that activation of these signaling pathways was mediated by the Shp-2 signaling pathway. These effects appear to be associated with activation of the Shp-2, ErK1/2 and Akt signaling pathways. Our results suggest that AC has antidepressant-like and neuroprotective (reducing infarct size) effects and that activation of pShp-2 and pErK1/2 pathways may be involved in the effects.