Optical Methods for the Measurement and Manipulation of Cytosolic Free Calcium in Neutrophils

The measurement and manipulation of cytosolic free Ca2+ permits the investigation of the mechanisms of generation of the Ca2+ signal and cellular responses to these Ca2+ signals within living neutrophils. The optical methods most applicable to neutrophils, which will be discussed here, are (1) the use of fluorescent indicators of Ca2+ and (2) photoactivation of reagents involved in Ca2+ signaling. Both of these synthetic agents can be loaded into neutrophils as lipid-soluble esters or can be microinjected into the cell. In this chapter, we will outline some of the techniques that have been used to monitor, visualize, and manipulate Ca2+ in neutrophils.