کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2039243 | 1073039 | 2016 | 7 صفحه PDF | دانلود رایگان |
• Excitation and inhibition are instantaneously balanced within a neuron
• This balance is disrupted at dendritic segment lengths of less than 50 μm
• The activity of only 22% of the spines is accompanied by somatic inhibition
• The inhibition-coupled activity tends to occur in large spine heads
SummaryThe dynamic interactions between synaptic excitation and inhibition (E/I) shape membrane potential fluctuations and determine patterns of neuronal outputs; however, the spatiotemporal organization of these interactions within a single cell is poorly understood. Here, we investigated the relationship between local synaptic excitation and global inhibition in hippocampal pyramidal neurons using functional dendrite imaging in combination with whole-cell recordings of inhibitory postsynaptic currents. We found that the sums of spine inputs over dendritic trees were counterbalanced by a proportional amount of somatic inhibitory inputs. This online E/I correlation was maintained in dendritic segments that were longer than 50 μm. However, at the single spine level, only 22% of the active spines were activated with inhibitory inputs. This inhibition-coupled activity occurred mainly in the spines with large heads. These results shed light on a microscopic E/I-balancing mechanism that operates at selected synapses and that may increase the accuracy of neural information.
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Journal: - Volume 14, Issue 6, 16 February 2016, Pages 1348–1354