Fig. 1.

Viability of kidney slices. Confocal images of kidney slices incubated with Hoechst and PI to label nuclei of all (ai) and dead (aii) cells, respectively. Overlay of images ai and aii demonstrates the ratio of live:dead cells (aiii). The corresponding brightfield image indicates the location of pericytes (aiv, black dotted lines) on a single vasa recta capillary (aiv, white dotted lines). Overlay of images ai–aiv shows all pericytes in this field of view are live (av). Calcein uptake is shown in tubules (t) and vasa recta capillaries (vr) in the renal medulla of live kidney slices (b). Pericytes (arrowhead) were also labelled by calcein (c).