Stanniocalcin-1 Regulates Extracellular ATP-Induced Calcium Waves in Human Epithelial Cancer Cells by Stimulating ATP Release from Bystander Cells
Figure 3
Trinucleotides from Injured Cells Were Required to Initiate Calcium Response.
A) Conditioned medium from viable (No Injury), mechanically disrupted (Injury) or mechanically disrupted lysate treated with 250 mU/mL apyrase for 10 min. (Injury + Apyrase) was placed on a confluent layer of Fluo-4 labeled A549 cells. Left column: Before addition of conditioned medium. Right column: 10 s after treatment with conditioned medium. Magnification = 4×. Inset for each: Pixel intensity profile for entire field of view. Inset images for each treatment group were manipulated equally using the threshold function in Adobe Photoshop in order to false color the peaks for clarity (red). n = 3 movies. B) Calcium response of 10 individual cells following addition of Injury or Injury + Apyrase (250 mU/mL for 10 min) treated conditioned medium. Black Arrow: Addition of conditioned medium. Red Arrow: Background Intensity Measurement. C) Average maximum intensity for individual cells after addition of No Injury, Injury, or Injury + Apyrase conditioned medium. * = p<0.05; n = 30.