['There are almost no data concerning the involvement of endoplasmic reticulum stress (Ca2+ fluxes) in the apoptosis of the pro-B cell type Ba/F3. Thus, we aimed the characterization of thapsigargin-induced effects on Ba/F3 cells in vitro.', 'For some experiments Ba/F3 cells were treated with 1 microM thapsigargin for 24 hours. To compare, we used as positive control the effects of valinomycin 10 microM. The negative control Ba/F3 cells received no treatment for 24 hours. After that, all batches of Ba/F3 cells were incubated in the presence of 1 mimcroM JC-1 (Sigma-Aldrich) at 37 degrees C for 30 minutes.', 'From the normal Ba/F3 JC-1-control cells (20.000 events gated by flow cytometry) 77.61 +/- 2.90% are associating high and 22.39 = 2.90% lower mitochondrial membrane potential. In the case of thapsigargin, 75.49 +/- 1.78% of the Ba/F3 cells are associating high and 24.51 +/- 1.78% lower mitochondrial membrane potential.'] Is thapsigargin-induced endoplasmic reticulum stress accompanied by mitochondrial membrane potential dissipation in murine pro-B cells?