Rise in cytosolic-free Ca⁺⁺ of 1-LN cells incubated with Pg 1.

Cells were preloaded with 4 μM fura-2 am for 20 minutes at 37°C, and changes in cytosolic- free Ca⁺⁺ were measured by digital imaging microscopy, as described in “Materials and methods.” Arrows indicate the times of addition of the ligands. (A) Effect of Pg 1 (0.2 μM). (B) Effect of Pg 1 (0.2 μM) following addition of Pg 2 (0.2 μM). (C) Effect of Pg 1 (0.2 μM) following addition of anti-TF IgG (10 μg/mL). (D) Effect of Pg 2 (0.2 μM) following addition of anti-TF IgG (10 μg/mL).