NINDS Electron Microscopy Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
Mol Brain. 2019 May 3;12(1):44. doi: 10.1186/s13041-019-0468-x.
Activity can induce structural changes in glutamatergic excitatory synapses, including increase in thickness and curvature of the postsynaptic density (PSD); these structural changes can only be documented by electron microscopy. Here in organotypic hippocampal slice cultures where experimental conditions can be easily manipulated, increases in thickness and curvature of PSDs were noticeable within 30 s of stimulation and progressed with time up to 3 min. These structural changes were reversible upon returning the samples to control medium for 5-10 min. Thus, the postsynaptic density is a very dynamic structure that undergoes rapid reorganization of its components upon stimulation, and recovery upon cessation of stimulation. The gradual increase in thickness of PSD could result from a gradual translocation of some PSD proteins to the PSD, and the increase in curvature of the PSD is likely led by postsynaptic elements.
活动可诱导谷氨酸能兴奋性突触的结构发生变化，包括突触后密度（PSD）厚度和曲率增加；这些结构变化只能通过电子显微镜来记录。在器官型海马切片培养物中，实验条件很容易被操纵，刺激后 30 秒内 PSD 的厚度和曲率增加明显，并在 3 分钟内随时间进展。将样品返回对照培养基 5-10 分钟后，这些结构变化是可逆的。因此，突触后密度是一种非常动态的结构，在受到刺激时其成分会迅速重新排列，刺激停止后会恢复。PSD 厚度的逐渐增加可能是由于一些 PSD 蛋白逐渐向 PSD 易位，而 PSD 曲率的增加可能是由突触后成分引起的。
