| First Author | Hage TA | Year | 2016 |
| Journal | Elife | Volume | 5 |
| PubMed ID | 27163179 | Mgi Jnum | J:247508 |
| Mgi Id | MGI:5927558 | Doi | 10.7554/eLife.13905 |
| Citation | Hage TA, et al. (2016) Electrical and Ca(2+) signaling in dendritic spines of substantia nigra dopaminergic neurons. Elife 5:e13905 |
| abstractText | Little is known about the density and function of dendritic spines on midbrain dopamine neurons, or the relative contribution of spine and shaft synapses to excitability. Using Ca(2+) imaging, glutamate uncaging, fluorescence recovery after photobleaching and transgenic mice expressing labeled PSD-95, we comparatively analyzed electrical and Ca(2+) signaling in spines and shaft synapses of dopamine neurons. Dendritic spines were present on dopaminergic neurons at low densities in live and fixed tissue. Uncaging-evoked potential amplitudes correlated inversely with spine length but positively with the presence of PSD-95. Spine Ca(2+) signals were less sensitive to hyperpolarization than shaft synapses, suggesting amplification of spine head voltages. Lastly, activating spines during pacemaking, we observed an unexpected enhancement of spine Ca(2+) midway throughout the spike cycle, likely involving recruitment of NMDA receptors and voltage-gated conductances. These results demonstrate functionality of spines in dopamine neurons and reveal a novel modulation of spine Ca(2+) signaling during pacemaking. |
