Fig. 4.

Tempol treatment suppresses RNS-induced DNA lesions in vitro. (A and B) Tempol treatment suppresses cellular nitrite (A) and 8-nitro-G (B) induced by ONOOCO₂⁻. Primary pancreatic acinar cells from the KPB mice were preincubated with mock or tempol (20, 50, and 100 µM) followed by the treatment of ONOOCO₂⁻. The level of 8-nitro-G was examined by mass spectrometry. (C) AP sites are remarkably reduced in the presence of tempol. Primary pancreatic acinar cells from KPB mice were preincubated with or without tempol followed by the treatment of ONOOCO₂⁻. (D and E) Tempol treatment suppresses RNS-induced DSBs. (D) Foci of γH2AX and 53BP1 in the primary pancreatic acinar cells from the KPB mice were examined. (Scale bars, 10 µm.) Foci numbers of γH2AX and 53BP1 in each cell are shown in the graph. (E) Primary pancreatic acinar cells from the KPB mice were preincubated with or without tempol (20, 50, and 100 µM). Neutral comet assays were performed to examine ONOOCO₂⁻-induced DSBs. Tail moments of the cells treated with different doses of tempol are shown in the histogram. Means and SDs were plotted. *P < 0.1; **P < 0.01; ***P < 0.001.