Majewska A, Tashiro A, Yuste R
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
J Neurosci. 2000 Nov 15;20(22):8262-8. doi: 10.1523/JNEUROSCI.20-22-08262.2000.
Dendritic spines receive most excitatory inputs in the CNS and compartmentalize calcium. Spines also undergo rapid morphological changes, although the function of this motility is still unclear. We have investigated the effect of spine movement on spine calcium dynamics with two-photon photobleaching of enhanced green fluorescent protein and calcium imaging of action potential-elicited transients in spines from layer 2/3 pyramidal neurons in mouse visual cortex slices. The elongation or retraction of the spine neck during spine motility alters the diffusional coupling between spine and dendrite and significantly changes calcium decay kinetics in spines. Our results demonstrate that the spine's ability to compartmentalize calcium is constantly changing.
树突棘在中枢神经系统中接收大部分兴奋性输入并分隔钙离子。树突棘还会经历快速的形态变化，尽管这种动态变化的功能仍不清楚。我们利用增强型绿色荧光蛋白的双光子光漂白技术以及对小鼠视觉皮层切片中第2/3层锥体神经元树突棘动作电位诱发瞬变的钙成像，研究了树突棘运动对树突棘钙动力学的影响。树突棘运动期间树突棘颈部的伸长或回缩会改变树突棘与树突之间的扩散耦合，并显著改变树突棘中的钙衰减动力学。我们的结果表明，树突棘分隔钙离子的能力在不断变化。
