Simultaneous sodium and calcium imaging from dendrites and axons
MetadataShow full item record
Dynamic calcium imaging is a major technique of neuroscientists. It can reveal information about the location of various calcium channels and calcium permeable receptors, the time course, magnitude, and location of intracellular calcium concentration ([Ca2+]i) changes, and indirectly, the occurrence of action potentials. Dynamic sodium imaging, a less exploited technique, can reveal analogous information related to sodium signaling. In some cases, like the examination of AMPA and NMDA receptor signaling, measurements of both [Ca2+]i and [Na+]i changes in the same preparation may provide more information than separate measurements. To this end, we developed a technique to simultaneously measure both signals at high speed and sufficient sensitivity to detect localized physiologic events. This approach has advantages over sequential imaging because the preparation may not respond identically in different trials. We designed custom dichroic and emission filters to allow the separate detection of the fluorescence of sodium and calcium indicators loaded together into a single neuron in a brain slice from the hippocampus of Sprague-Dawley rats. We then used high-intensity light emitting diodes (LEDs) to alternately excite the two indicators at the appropriate wavelengths. These pulses were synchronized with the frames of a CCD camera running at 500 Hz. Software then separated the data streams to provide independent sodium and calcium signals. With this system we could detect [Ca2+]i and [Na+]i changes from single action potentials in axons and synaptically evoked signals in dendrites, both with submicron resolution and a good signal-to-noise ratio (S/N).
© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in eNeuro 2 (2015): ENEURO.0092-15.2015, doi:10.1523/ENEURO.0092-15.2015.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Prolonged calcium influx after termination of light-induced calcium release in invertebrate photoreceptors Gomez, Maria del Pilar; Nasi, Enrico (Rockefeller University Press, 2009-08-31)In microvillar photoreceptors, light stimulates the phospholipase C cascade and triggers an elevation of cytosolic Ca2+ that is essential for the regulation of both visual excitation and sensory adaptation. In some organisms, ...
Sodium and glucose transport across the in vitro perfused midgut of the blue crab, Callinectes sapidus Rathbun Chu, Ka Hou (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1984-01)The principal objectives of the present study are: (1) to investigate sodium transport across the midgut as well as the hindgut of Callinectes sapidus and the functioning of these two regions of the gut in osmotic and ...
Barzilai, Maya Gur; Reitzel, Adam M.; Kraus, Johanna E. M.; Gordon, Dalia; Technau, Ulrich; Gurevitz, Michael; Moran, Yehu (Cell Press, 2012-08-30)Ion selectivity of metazoan voltage-gated Na+ channels is critical for neuronal signaling and has long been attributed to a ring of four conserved amino acids that constitute the ion selectivity filter (SF) at the channel ...