Fig. 5

Heterologous desensitization between ADP and UTP also occurs in hematopoietic progenitor cells. Cells were loaded with the Ca²⁺ indicator fluo-4, and intensity was measured with confocal microscopy (LSM 510 META). Scale bar = 20 μM. The images are a pseudocolored representation in reference to the fluorescence intensity scale (0 = black, 255 = white). a Images in two Z planes showed cell preparations before agonist addition (basal) and after stimulation (max) with 1 mM of ADP and UTP. b Records of fluorescence intensity as a function of time corresponded to images of hematopoietic and stromal cells in a, and represented responses of four independent experiments