Simultaneous Voltage and Calcium Imaging from Primary Sensory Neurons in Live Mice
Abstract
Primary sensory neurons are responsible for encoding and processing the sensory information, i.e. onset, intensity, duration, and location from peripheral stimuli, into electrical signals for pain information processing. In vivo intact dorsal root ganglia (DRG) imaging using genetically-encoded Ca2+ indicators (GECIs) has been successfully established in our lab, which permit simultaneous imaging of thousands of primary sensory neurons per DRG in live mice. This method allows us to study DRG populational neuronal activity within their native environment. However, GECI imaging has some misleading aspects. For example, Ca2+ indicators fail to distinguish between action potential-evoked Ca2+ influx versus Ca2+ transients arising from internal stores and ligand-gated Ca2+ channels. Furthermore, Ca2+ indicators only report suprathreshold(spiking) signaling but failing to detect subthreshold depolarizations (non-spiking) and hyperpolarizing (inhibitory) events. Finally, Ca2+ indicator slack the ability to distinguish single or multiple action potentials-induced Ca2+ transients due to slow kinetics and limited sensitivity. Recently, our lab successfully developed an innovative in vivo voltage imaging system that allows us to detect changes in sub- and suprathreshold voltage dynamics in DRG across different pain conditions. The availability of in vivo voltage and Ca2+ imaging encourages us to seek the potential link between sub- and/or suprathreshold voltage signals and their relating Ca2+ events in primary sensory neurons. Knowing the correlation between the voltage and Ca2+ signals will strengthen the interpretation of Ca2+ imaging studies that have been widely used, and greatly facilitate studies on the function of DRG neuronal circuits.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2023
- Accession Number
- AD1201008
Entities
People
- Yan Zhang
Organizations
- University of Texas Health Science Center at San Antonio