Fig. 1. Distribution of cPLA₂- in resting and A23817-stimulated A549 cells. (A) cPLA₂- was detected in A549 cell lysates (20 µg protein) using a goat polyclonal antibody (lane 1). Also shown is the control corresponding to goat polyclonal antibody pre-incubated with blocking peptide (lane 2). (B) Cells were grown on coverslips and incubated with buffer alone (control) or stimulated with 5 µM A23187 (in HEPES/Tyrode's buffer) in the presence of 1 mM extracellular Ca²⁺ for 1 minute. Cells were then fixed and permeabilized, and cPLA₂- was detected using immunofluorescence microscopy. Bar, 10 µm.