Histamine inhibits the generation of ROS in CML cells: reversal by ranitidine.

CML cells were treated with culture medium (control, ○), histamine (10 μmol/L, ●), ranitidine (10 μmol/L, ▵) and histamine + ranitidine (10 μmol/L + 10 μmol/L, ▴). Emission of chemiluminescence was recorded after addition of fMLF at t = 0. Abscissa, time of study (minute); ordinate, chemiluminescence in cpm. Similar results were obtained in experiments using CML cells from 4 patients with CML.