Sheng li ke xue jin zhan [Progress in physiology]
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Sheng Li Ke Xue Jin Zhan · Oct 2007
Review[Alternative tactile system: C-fibers coding the affective aspect].
It has been accepted that human tactile sensation is mediated exclusively by large myelinated (Abeta) fibres. Nevertheless, recent studies indicated a dual mechanoceptive innervation of the skin in various mammals. Besides the known A fibers, the skin is also innervated by slow-conducting, low-threshold, small unmyelinated (C) afferents. ⋯ Functional magnetic resonance imaging (fMRI) studies showed that a slowly moving tactile stimulus along hairy skin produced a strong activation of the insular cortex. Pleasant touch has also been demonstrated to activate orbitofrontal cortex adjacent to areas responding to pleasant taste and smell. Overall, the response characteristics and activated brain regions suggest that they are related with the limbic system and affective aspect rather than tactile discriminative function.
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Sheng Li Ke Xue Jin Zhan · Apr 2007
Review[The updated advancements in synaptic plasticity mediated by glial cells].
Synaptic plasticity is the basis of learning and memory and extensive studies focused on neurons and synapses whereas glial cells are neglected for a long time. Recent studies indicate that glial cells can be involved in the formation of tripartite synapse and affect the activities of synapse, and thereby the roles of glial cells in synaptic plasticity have'been noticed gradually. There are evidences that astrocytes, microglia and oligodendrocytes can modulate the synaptic plasticity via multiple signaling pathways, including glutamate, serine, glycine and ATP et al. These studies have provided new directions for the synaptic plasticity study and will contribute greatly to the clarification of the synaptogenesis and learning and memory.
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Sheng Li Ke Xue Jin Zhan · Apr 2006
Review[Distribution of ion channels in pulmonary arterial smooth muscle cells and their roles in hypoxia pulmonary vasoconstriction].
Hypoxic pulmonary vasoconstriction (HPV) is the rapid, reversible increase in pulmonary vascular resistance that occurs when the alveolar oxygen tension falls below a threshold level, thereby achieving ventilation/perfusion matching. HPV is closely related to the state of K+, Ca2+ and Cl- channels in pulmonary arterial smooth muscle cells, which distribute heterogeneously along the longitude of pulmonary artery tree, and cause heterogeneous vasoconstriction response in different part of pulmonary artery in HPV. In this review we summarize current knowledge about the distribution of these ion channels and their roles in HPV.