Biomedical Engineering Reference
In-Depth Information
Chapter 5
In Vivo Ca
2+
Imaging of Neuronal Activity
Hiroto Ogawa and John P. Miller
Abstract
Optical recording that provides both anatomical and physiological data
has become an essential research technique for neuroethological studies. In particu-
lar, Ca
2+
imaging is one of the most popular and useful methods for visualization of
spatiotemporal dynamics of neuronal activity. Because Ca
2+
is involved in so many
fundamental neuronal signaling functions, including transmitter release and induc-
tion of synaptic plasticity, Ca
2+
imaging can yield information that is crucial for a
thorough understanding of these processes. In this chapter, we summarize aspects of
Ca
2+
-sensitive dyes that must be considered during the selection of an appropriate
indicator for the specifi c question being investigated. We also discuss the develop-
ment of dye-loading protocols, experimental designs, and optical system confi gura-
tions that are required to enable the effective use of these Ca
2+
-sensitive indicators.
As an example application, we demonstrate how Ca
2+
imaging of the cricket cercal
sensory system in vivo has enabled us to monitor pre- and postsynaptic activity
simultaneously on specifi c dendrites of an identifi ed neuron.
Keywords
Ca
2+
imaging • Confocal microscope • Fluorescent Ca
2+
-sensitive dye •
Imaging device • In vivo imaging • Ratiometric imaging • Two-photon microscope
