Figure 3.

Proximal tubule– and endothelial-specific pannexin1^−/− (Panx1^−/−) mice are protected against renal ischemia-reperfusion injury (IRI). (A) Bone marrow chimeras show that nonhematopoietic cells are responsible for protection against IRI in Panx1^−/− mice. Plasma creatinine values in bone marrow chimeras of Panx1^+/+ (wild type [WT]) and Panx1^−/− (knockout [KO]) mice subjected to 26 minutes of bilateral IRI and 24 hours of reperfusion are shown (n=8–10 per group). ****P<0.001. (B–F) PepckCrerePanx1^f/f (KO; n=7), PepckCcrePanx1^wt/wt (WT; n=7; [B, D, and F] proximal tubule–specific KO and WT controls), VeCadCreER^T2+Panx1^f/f (KO; n=10), and VeCadCreER^T2+Panx1^wt/wt (WT; n=6; [C, E, and G] tamoxifen-inducible endothelial-specific KO and WT controls) mice were subjected to 26 minutes of bilateral IRI or sham operation and 24 hours of reperfusion. Sham operations were performed using PepckCrePanx1^wt/wt or PepckCrePanx^f/wt littermates. Experimental design for B, D, and F is in Supplemental Figure 2B, and experimental design for C, E, and F is in Supplemental Figure 2C. (B and C) Plasma creatinine values of proximal tubule and endothelial Panx1^−/− mice, respectively. ***P<0.001; ****P<0.001. (D and E) Quantification of acute tubular necrosis (ATN; percentage of outer medulla area) in hematoxylin and eosin–stained kidney sections of proximal tubule and endothelial Panx1^−/− mice, respectively. **P<0.01; ***P<0.001; ****P<0.001. (F) Neutrophil infiltration is decreased in Panx1 tissue-specific KO mice. After IRI, kidneys of PepckCrePanx1^f/f, VdCadCreER^T2+Panx1^f/f, and appropriate control mice were immunolabeled for the presence of neutrophils (red; 7/4 immunoreactivity) as described in Methods. Representative micrographs of outer medulla area are presented. Blue indicates 4′,6-diamidino-2-phenylindole-labeled nuclei. Green indicates kidney autofluorescence adjusted to reveal tubule architecture. Scale bars, 100 μm; 25 μm in insets.