Fig. 1.

dDAVP significantly reduces the level of bromodeoxyuridine (BrdU)-labeled DNA breaks in staurosporine-treated cells. Mouse cortical collecting duct cells (mpkCCD) were incubated in the absence (control; A–C) or presence (dDAVP; D–F) of 0.1 nM dDAVP for 3 h in the presence of 1 μM staurosporine (SS). Cells were then fixed and assayed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). A and D: propidium iodide staining of total cellular DNA. B and E: EdUTP-labeled DNA breaks; C and F: merged images. G: the average number of EdUTP-labeled cells per field (i.e., cells undergoing apoptosis) were measured for each condition. Values for cells incubated in the absence of staurosporine (DMSO vehicle) are also shown to indicate baseline levels of apoptosis in the presence and absence of dDAVP. Fields = 15 (5 fields each from 3 biological replicates); ×63 objective; scale bar = 10 μm. ***P < 0.001.