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. 1994 Aug 16;91(17):8170–8174. doi: 10.1073/pnas.91.17.8170

Visualizing hippocampal synaptic function by optical detection of Ca2+ entry through the N-methyl-D-aspartate channel.

R Malinow 1, N Otmakhov 1, K I Blum 1, J Lisman 1
PMCID: PMC44567  PMID: 7914703

Abstract

Fura-2 and imaging technology were used to detect intracellular Ca2+ changes in CA1 pyramidal cells in hippocampal slices. During focal synaptic stimulation, one or more highly localized regions of Ca2+ elevation (hot spots) were detected in the dendrites. Ca2+ spread from the center of hot spots with properties consistent with diffusion. Several lines of evidence indicate that these hot spots were due to Ca2+ entry through N-methyl-D-aspartate synaptic channels. The spatial and temporal resolution of the method was sufficient to detect the response of single hot spots to single stimuli, thus providing a real-time method for monitoring local synaptic activity. Using this method, we show that synapses on the same dendrite differ in their probability of response and in their facilitation properties.

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Selected References

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