Probing Ca release mechanisms using sea urchin egg homogenates.

Sea urchin eggs have been extensively used to study Ca release through intracellular Ca-permeable channels. Their amenability to homogenization yields a robust, cell-free preparation that was central to establishing the Ca mobilizing actions of cyclic ADP-ribose and NAADP. Egg homogenates have continued to provide insight into the basic properties and pharmacology of intracellular Ca release channels. In this chapter, we describe methods for the preparation of egg homogenates and monitoring Ca release using fluorimetry and radiotracer flux.