Effects of ATP on intracellular Ca⁺⁺transients in eosinophils.

(A) Cells were labeled with fura-2 and stimulated in the absence of EGTA with ATP in three concentrations: 1 mmol/L (——), 100 μmol/L (-—-), and 10 μmol/L (—-). Representative data of 1 experiment are shown. The experiments were repeated 5 times with similar results. (B) Cells were labeled with fura-2 and stimulated in the absence (-—-) or presence (——) of 4 mmol/L EGTA with 100 μmol/L ATP. (C) Eosinophils were pretreated without (——) or with (—-) 300 μmol/L oxidized ATP for 2 hours at 37°C, labeled with fura-2, and stimulated with 100 μmol/L ATP.