Odor-evoked oxygen consumption by action potential and synaptic transmission in the olfactory bulb.
Odor-evoked oxygen consumption by action potential and synaptic transmission in the olfactory bulb.
复制标题
DOI：
10.1523/jneurosci.4817-08.2009
复制
发表时间：
2009-02-04
期刊：
影响因子：
--
通讯作者：
Charpak S
中科院分区：
文献类型：
--
作者：
Lecoq J;Tiret P;Najac M;Shepherd GM;Greer CA;Charpak S
神经元活性代谢、微血管组织和血流动力学之间的关系对于解释脑功能成像至关重要。在这里，我们使用大鼠背侧嗅球作为模型，以确定在体内的动作电位传播，突触传递，耗氧量和毛细血管密度在气味刺激过程中的相关性。我们发现，毛细血管腔约占肾小球体积的3%，在那里发生突触传递，而只有0.1%的覆盖神经层。在肾小球中，气味触发局部早期组织氧分压降低，这主要是由于树突状细胞激活，而不是轴突末端的放电、递质释放或星形胶质细胞激活。在神经层中，动作电位传播不会产生组织氧分压的局部变化。我们的结论是，毛细血管密度与突触传递的氧化代谢密切相关，并建议动作电位传播主要是厌氧操作。
The relationship between metabolism of neuronal activity, microvascular organization and blood flow dynamics is critical for interpreting functional brain imaging. Here we used the rat dorsal olfactory bulb as a model to determine in vivo the correlation between action potential propagation, synaptic transmission, oxygen consumption and capillary density during odor stimulation. We find that capillary lumen occupies about 3 % of the glomerular volume, where synaptic transmission occurs, and only 0.1 % of the overlying nerve layer. In glomeruli, odor triggers a local early decrease in tissue oxygen partial pressure that results principally from dendritic activation rather than from firing of axon terminals, transmitter release or astrocyte activation. In the nerve layer, action potential propagation does not generate local changes in tissue oxygen partial pressure. We conclude that capillary density is tightly correlated with the oxidative metabolism of synaptic transmission, and suggest that action potential propagation operates mainly anaerobically.