Fig. 8. Immunochemical analysis of CgA domain-GFP fusion protein release upon stimulation of regulated secretion. PC12 cells were transiently transfected with expression plasmids encoding the GFP fusion proteins indicated. 48 hours after transfection, regulated secretion was triggered by 2 mM BaCl₂ for 15 minutes. Extracellular media were collected and concentrated using C-18 SepPak cartridges, and processed for immunoblot using an anti-GFP antibody. Immunoreactivity was visualized by chemiluminescence.