Department of Neurosciences, Medical University of South Carolina Charleston, SC, USA.
Front Syst Neurosci. 2011 Nov 24;5:94. doi: 10.3389/fnsys.2011.00094. eCollection 2011.
Extracellular glutamate of glial origin modulates glial and neuronal glutamate release and synaptic plasticity. Estimates of the tonic basal concentration of extracellular glutamate range over three orders of magnitude (0.02-20 μM) depending on the technology employed to make the measurement. Based upon binding constants for glutamate receptors and transporters, this range of concentrations translates into distinct physiological and pathophysiological roles for extracellular glutamate. Here we speculate that the difference in glutamate measurements can be explained if there is patterned membrane surface expression of glutamate release and transporter sites creating extracellular subcompartments that vary in glutamate concentration and are preferentially sampled by different technologies.
胶质细胞来源的细胞外谷氨酸调节胶质细胞和神经元谷氨酸释放和突触可塑性。根据所采用的测量技术，细胞外谷氨酸的基础静息浓度估计值跨越三个数量级（0.02-20μM）。根据谷氨酸受体和转运体的结合常数，这个浓度范围转化为细胞外谷氨酸的不同生理和病理生理作用。在这里，我们推测如果谷氨酸释放和转运位点的膜表面表达具有模式化，形成细胞外亚区室，其谷氨酸浓度不同，并且被不同的技术优先采样，那么谷氨酸测量值的差异可以得到解释。
