神经损伤与功能重建
神經損傷與功能重建
신경손상여공능중건
NEURAL INJURY AND FUNCTIONAL RECONSTRUCTION
2014年
6期
501-501
,共1页
唐颖馨(编译)%Fern RF%Matute C
唐穎馨(編譯)%Fern RF%Matute C
당영형(편역)%Fern RF%Matute C
三磷酸腺苷%星形胶质细胞%轴突%神经胶质%谷氨酸%少突胶质细胞
三燐痠腺苷%星形膠質細胞%軸突%神經膠質%穀氨痠%少突膠質細胞
삼린산선감%성형효질세포%축돌%신경효질%곡안산%소돌효질세포
ATP%astrocyte%axon%glia%glutamate%oligodendrocyte
脑白质是由许多有髓鞘的轴突组成,白质和灰质共同组成中枢神经系统,白质是中枢神经系统内信息快速传递的基础。有髓神经通路主要是由少突胶质细胞、星形胶质细胞及少量的小胶质细胞和少突胶质前体细胞构成。大部分白质内的神经递质信号主要存在于神经细胞胞体外,这提示这些神经递质除了具有完成神经元与神经元之间信息传递的功能外,还有其他生理功能。白质中的神经递质信号种类很多,已经证实的有谷氨酸能、嘌呤能(ATP和腺苷)、GABA能、甘氨酸能、肾上腺素能、胆碱能、多巴胺能、血清素能等信号递质,通过与各种离子型或代谢型受体结合发挥作用。轴突和胶质细胞都可以释放神经递质,也可以表达相应的受体。白质内神经递质信号的生理功能还需进一步研究,但研究已经证实谷氨酸和ATP介导的信号可激活胶质细胞上的钙离子通道,并调节轴突的传导功能。某项研究显示,在动作电位传播的过程中,轴突释放神经递质并与胶质细胞上的受体结合,通过少突胶质细胞来调节星形胶质细胞的稳态和髓鞘形成。星形胶质细胞也释放神经递质,与轴突上的受体相结合,增强动作电位的传播,维持信号电位沿长的轴突传播。白质内神经递质种类的多样性,提示它们有多种功能,对信号的传递有重要作用。白质内的神经递质信号现象很有可能也存在于大脑皮质和灰质,在这些部位的神经递质对于大脑的高级认知功能有更重要的作用。
腦白質是由許多有髓鞘的軸突組成,白質和灰質共同組成中樞神經繫統,白質是中樞神經繫統內信息快速傳遞的基礎。有髓神經通路主要是由少突膠質細胞、星形膠質細胞及少量的小膠質細胞和少突膠質前體細胞構成。大部分白質內的神經遞質信號主要存在于神經細胞胞體外,這提示這些神經遞質除瞭具有完成神經元與神經元之間信息傳遞的功能外,還有其他生理功能。白質中的神經遞質信號種類很多,已經證實的有穀氨痠能、嘌呤能(ATP和腺苷)、GABA能、甘氨痠能、腎上腺素能、膽堿能、多巴胺能、血清素能等信號遞質,通過與各種離子型或代謝型受體結閤髮揮作用。軸突和膠質細胞都可以釋放神經遞質,也可以錶達相應的受體。白質內神經遞質信號的生理功能還需進一步研究,但研究已經證實穀氨痠和ATP介導的信號可激活膠質細胞上的鈣離子通道,併調節軸突的傳導功能。某項研究顯示,在動作電位傳播的過程中,軸突釋放神經遞質併與膠質細胞上的受體結閤,通過少突膠質細胞來調節星形膠質細胞的穩態和髓鞘形成。星形膠質細胞也釋放神經遞質,與軸突上的受體相結閤,增彊動作電位的傳播,維持信號電位沿長的軸突傳播。白質內神經遞質種類的多樣性,提示它們有多種功能,對信號的傳遞有重要作用。白質內的神經遞質信號現象很有可能也存在于大腦皮質和灰質,在這些部位的神經遞質對于大腦的高級認知功能有更重要的作用。
뇌백질시유허다유수초적축돌조성,백질화회질공동조성중추신경계통,백질시중추신경계통내신식쾌속전체적기출。유수신경통로주요시유소돌효질세포、성형효질세포급소량적소효질세포화소돌효질전체세포구성。대부분백질내적신경체질신호주요존재우신경세포포체외,저제시저사신경체질제료구유완성신경원여신경원지간신식전체적공능외,환유기타생리공능。백질중적신경체질신호충류흔다,이경증실적유곡안산능、표령능(ATP화선감)、GABA능、감안산능、신상선소능、담감능、다파알능、혈청소능등신호체질,통과여각충리자형혹대사형수체결합발휘작용。축돌화효질세포도가이석방신경체질,야가이표체상응적수체。백질내신경체질신호적생리공능환수진일보연구,단연구이경증실곡안산화ATP개도적신호가격활효질세포상적개리자통도,병조절축돌적전도공능。모항연구현시,재동작전위전파적과정중,축돌석방신경체질병여효질세포상적수체결합,통과소돌효질세포래조절성형효질세포적은태화수초형성。성형효질세포야석방신경체질,여축돌상적수체상결합,증강동작전위적전파,유지신호전위연장적축돌전파。백질내신경체질충류적다양성,제시타문유다충공능,대신호적전체유중요작용。백질내적신경체질신호현상흔유가능야존재우대뇌피질화회질,재저사부위적신경체질대우대뇌적고급인지공능유경중요적작용。
White matter (WM) tracts are bundles of myelinated axons that provide for rapid communication throughout the CNS and integration in grey matter (GM). The main cells in myelinated tracts are oligodendrocytes and astrocytes, with small populations of microglia and oligodendrocyte precursor cells. The prominence of neurotransmitter signaling in WM, which largely exclude neuronal cell bodies, indicates it must have physiological functions other than neuron-to-neuron communication. A surprising aspect is the diversity of neurotransmitter signaling in WM, with evidence for glutamatergic, purinergic (ATP and adenosine), GABAergic, glycinergic, adrenergic, cholinergic, dopaminergic and serotonergic signaling, acting via a wide range of ionotropic and metabotropic receptors. Both axons and glia are potential sources of neurotransmitters and may express the respective receptors. The physiological functions of neurotransmitter signaling in WM are subject to debate, but glutamate and ATP-mediated signaling have been shown to evoke Ca (2+) signals in glia and modulate axonal conduction. Experimental findings support a model of neurotransmitters being released from axons during action potential propagation acting on glial receptors to regulate the homeostatic functions of astrocytes and myelination by oligodendrocytes. Astrocytes also release neurotransmitters, which act on axonal receptors to strengthen action potential propagation, maintaining signaling along potentially long axon tracts. The co-existence of multiple neurotransmitters in WM tracts suggests they may have diverse functions that are important for information processing. Furthermore, the neurotransmitter signaling phenomena described in WM most likely apply to myelinated axons of the cerebral cortex and GM areas, where they are doubtless important for higher cognitive function.