Astrocytes modulate neural network activity by Ca²+-dependent uptake of extracellular K+.
Astrocytes modulate neural network activity by Ca²+-dependent uptake of extracellular K+.
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DOI：
10.1126/scisignal.2002334
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发表时间：
2012-04-03
影响因子：
7.3
通讯作者：
Nedergaard M
中科院分区：
文献类型：
--
作者：
Wang F;Smith NA;Xu Q;Fujita T;Baba A;Matsuda T;Takano T;Bekar L;Nedergaard M
星形胶质细胞是电不可兴奋的细胞，在各种神经递质和神经调节剂的作用下，细胞内钙离子（Ca2+）增加。然而，星形细胞Ca2+信号的生理作用仍然存在争议。我们在这里表明，星形细胞Ca2+信号在体内和体外都刺激了Na+，K+- atp酶（Na+和K+依赖的腺苷三磷酸酶），导致细胞外钾离子（K+）浓度的短暂降低。这反过来导致神经元超极化和抑制基线兴奋性突触活动，检测到兴奋性突触后电流的频率降低。突触故障同时减少，导致突触保真度增加。最终结果是星形胶质细胞通过主动摄取K+，提高了突触传递的信噪比。因此，主动控制细胞外K+浓度为星形胶质细胞提供了一种简单而强大的机制来快速调节网络活动。
Astrocytes are electrically nonexcitable cells that display increases in cytosolic calcium ion (Ca2+) in response to various neurotransmitters and neuromodulators. However, the physiological role of astrocytic Ca2+ signaling remains controversial. We show here that astrocytic Ca2+ signaling ex vivo and in vivo stimulated the Na+,K+-ATPase (Na+- and K+-dependent adenosine triphosphatase), leading to a transient decrease in the extracellular potassium ion (K+) concentration. This in turn led to neuronal hyperpolarization and suppressed baseline excitatory synaptic activity, detected as a reduced frequency of excitatory postsynaptic currents. Synaptic failures decreased in parallel, leading to an increase in synaptic fidelity. The net result was that astrocytes, through active uptake of K+, improved the signal-to-noise ratio of synaptic transmission. Active control of the extracellular K+ concentration thus provides astrocytes with a simple yet powerful mechanism to rapidly modulate network activity.
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DOI：
10.1073/pnas.95.26.15735
发表时间：
1998-12-22
影响因子：
11.1
作者：
Cotrina, ML;Lin, JHC;Nedergaard, M
通讯作者：
Nedergaard, M
影响因子：
16.2
作者：
Geiger, JRP;Jonas, P
通讯作者：
Jonas, P
影响因子：
2.5
作者：
D'Ambrosio, R;Gordon, DS;Winn, HR
通讯作者：
Winn, HR
影响因子：
5.5
作者：
Golovina, VA
通讯作者：
Golovina, VA
影响因子：
5.5
作者：
Han, Fei;Bossuyt, Julie;Bers, Donald M.
通讯作者：
Bers, Donald M.