Korkotian E, Segal M
Department of Neurobiology, The Weizmann Institute, Rehovot, Israel.
Hippocampus. 2000;10(5):587-95. doi: 10.1002/1098-1063(2000)10:5<587::AID-HIPO9>3.0.CO;2-C.
The recent use of novel high-resolution imaging methods of living neurons in vitro has led to a change in the view of the dendritic spine, from a stable, long-term memory storage device to that of a dynamic structure, which can undergo fast morphological changes over periods of hours and even minutes. While the functional significance of these changes in spine dimensions is still obscure, we have obtained evidence to indicate that the length of the spine has a critical role in determining the degree of interaction between the spine head and the parent dendrite, such that longer spines are more independent of the parent dendrite than the short ones. We have now studied the role of intracellular calcium stores in determining the magnitude and time course of spine responses to a calcium surge evoked in response to glutamate, which causes an influx of calcium, and the results indicate that spine morphology has an important role in determining the involvement of the stores in calcium responses. Since spines can change their length over a rather short time, these results indicate that changes in spine length serve to fine-tune the interaction between the spine head and the parent dendrite on a continuous basis.
近期，体外活神经元新型高分辨率成像方法的应用使人们对树突棘的看法发生了改变，从一个稳定的长期记忆存储装置转变为一个动态结构，它能够在数小时甚至数分钟内快速发生形态变化。虽然这些棘突尺寸变化的功能意义仍不明确，但我们已获得证据表明，棘突的长度在决定棘突头部与母树突之间相互作用的程度方面起着关键作用，即较长的棘突比较短的棘突更独立于母树突。我们现在研究了细胞内钙库在决定棘突对谷氨酸诱发的钙激增反应的幅度和时间进程中的作用，谷氨酸会导致钙内流，结果表明棘突形态在决定钙库参与钙反应方面具有重要作用。由于棘突能够在相当短的时间内改变其长度，这些结果表明，棘突长度的变化有助于持续微调棘突头部与母树突之间的相互作用。
