Fig. 1.

Hypoxia-inducible factor-1α (HIF-1α) immunofluorescence. To demonstrate that HIF-1α is present in the cells lining the cysts, immunofluorescence was performed. There is HIF-1α staining (red) in tubular epithelial cells of normal controls. There is HIF-1α staining (red) in cells lining the cysts in Cy/+ and Cy/Cy rats. HIF-1α is known to be a nuclear protein. Nuclei are represented by blue (DAPI) staining. Superimposed red and blue staining indicates localization of HIF-1α staining to the nucleus.