Journal
JOURNAL OF NEUROSCIENCE
Volume 37, Issue 41, Pages 9964-9976Publisher
SOC NEUROSCIENCE
DOI: 10.1523/JNEUROSCI.1758-17.2017
Keywords
AMPA receptor; dendrite; hippocampus; NMDA receptor; sodium imaging; spine
Categories
Funding
- National Institutes of Health [R21NS085729, R01NS099122]
Ask authors/readers for more resources
Dendritic spines are key elements underlying synaptic integration and cellular plasticity, but many features of these important structures are not known or are controversial. We examined these properties using newly developed simultaneous sodium and calcium imaging with single-spine resolution in pyramidal neurons in rat hippocampal slices from either sex. Indicators for both ions were loaded through the somatic patch pipette, which also recorded electrical responses. Fluorescence changes were detected with a high-speed, low-noise CCD camera. Following subthreshold electrical stimulation, postsynaptic sodium entry is almost entirely through AMPA receptors with little contribution from entry through NMDA receptors or voltage-gated sodium channels. Sodium removal from the spine head is through rapid diffusion out to the dendrite through the spine neck with a half-removal time of similar to 16 ms, which suggests the neck has low resistance. Peak [Na+](i) changes during single EPSPs are similar to 5mM. Stronger electrical stimulation evoked small plateau potentials that had significant longer-lasting localized [Na+](i) increases mediated through NMDA receptors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available