Probing Ca2 + release mechanisms using sea urchin egg homogenates

Abstract Sea urchin eggs have been extensively used to study Ca 2 + release through intracellular Ca 2 + -permeable channels. Their amenability to homogenization yields a robust, cell-free preparation that was central to establishing the Ca 2 + mobilizing actions of cyclic ADP-ribose and NAADP. Egg homogenates have continued to provide insight into the basic properties and pharmacology of intracellular Ca 2 + release channels. In this chapter, we describe methods for the preparation of egg homogenates and monitoring Ca 2 + release using fluorimetry and radiotracer flux.