Agonist-induced SpH-MOR exocytic events in HEK293 cells. Time-lapse video of HEK293 cells stably expressing SpH-MOR without treatment (baseline) or after 10 min 12.5 µM DAMGO treatment (post-agonist) recorded using TIR-FM at 0.1 s per frame for 60 s for each treatment condition. A 120-frames blank gap was inserted in the video between the two conditions to denote the 10 min treatment time. Recording was resumed on the same field after the treatment. Yellow circles in the post-agonist section mark selected exocytic events (puffs) that show characteristics of instantaneous increase in fluorescence followed by diffusion. Video is displayed at 30 frames per second.
