Role of astrocytes in the clearance of excess extracellular potassium

被引:351
作者
Walz, W [1 ]
机构
[1] Univ Saskatchewan, Dept Physiol, Saskatoon, SK S7N 5E5, Canada
关键词
D O I
10.1016/S0197-0186(99)00137-0
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The development of concepts describing potassium clearance mechanisms in the mammalian central nervous system in the last 35 years is reviewed. The pattern of excess potassium in the extracellular space is discussed as are the implications of these potassium levels for neuronal excitability. There is a systematic description of the available evidence for astrocytic involvement in situ. The three possible astrocytic potassium clearance mechanisms are introduced: spatial buffer mechanism; carrier-operated potassium chloride uptake as well as channel-operated potassium chloride uptake. The three mechanisms are compared and their compatibility is discussed. Evidence is now available showing that at least two of these if not all three mechanisms co-exist and complement each other. Finally, it is concluded that these potassium movements are not used as a signal system, only as a homeostatic feedback mechanisms. Such a genuine signal. system involving glial elements exists - but it is based on calcium waves. (C) 2000 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:291 / 300
页数:10
相关论文
共 81 条
[1]  
ADELMAN WJ, 1975, FED PROC, V34, P1322
[2]   THE EFFECTS OF MODERATE CHANGES OF EXTRACELLULAR K-+ AND CA-2+ ON SYNAPTIC AND NEURAL FUNCTION IN THE CA1 REGION OF THE HIPPOCAMPAL SLICE [J].
BALESTRINO, M ;
AITKEN, PG ;
SOMJEN, GG .
BRAIN RESEARCH, 1986, 377 (02) :229-239
[3]   ION ACTIVITIES AND POTASSIUM UPTAKE MECHANISMS OF GLIAL-CELLS IN GUINEA-PIG OLFACTORY CORTEX SLICES [J].
BALLANYI, K ;
GRAFE, P ;
TENBRUGGENCATE, G .
JOURNAL OF PHYSIOLOGY-LONDON, 1987, 382 :159-174
[4]  
Ballanyi Klaus, 1995, P289
[5]   ION CHANNEL EXPRESSION BY WHITE MATTER GLIA - THE O-2A GLIAL PROGENITOR-CELL [J].
BARRES, BA ;
KOROSHETZ, WJ ;
SWARTZ, KJ ;
CHUN, LLY ;
COREY, DP .
NEURON, 1990, 4 (04) :507-524
[6]   Evidence for chloride ions as intracellular messenger substances in astrocytes [J].
Bekar, LK ;
Walz, W .
JOURNAL OF NEUROPHYSIOLOGY, 1999, 82 (01) :248-254
[7]  
Bekar LK, 1999, GLIA, V26, P129, DOI 10.1002/(SICI)1098-1136(199904)26:2<129::AID-GLIA4>3.0.CO
[8]  
2-7
[9]   MODIFICATION OF POTASSIUM MOVEMENT THROUGH THE RETINA OF THE DRONE (APIS-MELLIFERA-MALE) BY GLIAL UPTAKE [J].
COLES, JA ;
ORKAND, RK .
JOURNAL OF PHYSIOLOGY-LONDON, 1983, 340 (JUL) :157-174
[10]  
DERMIETZEL R, 1991, J NEUROSCI, V11, P1421