Figure 1.

(A through C) Live rat kidney slice loaded with calcein and excited at 800 nm to demonstrate viability and showing glomerulus (A), cortical medullary ray (B), and medulla (C). (D) In addition to differing morphology, PTs and DTs can be further distinguished by the green autofluorescence emission pattern when excited at 800 nm. Antibody labeling in fixed slices of kidney was used in initial experiments to confirm the identity of nephron sections. (E) Anti–Tamm-Horsfall protein (red) staining in DTs demonstrated the clear difference in morphology from PTs (green autofluorescence) in the slice preparation. (F) Anti–aquaporin 1 (green) staining was used to confirm the identity of PTs. Arrowhead, PT; arrow, DT. Bar = 20 μm.