Figure 4.

Competitive binding confocal microscopy experiments with renal proximal tubules (RPT) isolated from normal rats (N=4 for each experiment). The experiment was repeated 4 separate times using new fresh kidneys every time. For each experiment and each condition measurements from 3 separate wells in a 96-well plate were averaged. Panel A. Effects of cGMP binding on bodipy-oubain (B-OUA) binding. () Control: Opti-MEM. () B-OUA: 2 μM. () B-OUA + cGMP: (0.5 μM). () B-OUA + cGMP (1.0 μM). () B-OUA + cGMP (10 μM). Control fluorescence values represent background. All other results are reported as B-OUA fluorescence intensity above background. Panel B. Effects of OUA binding biotinylated cGMP (BIO-cGMP). () Control: Opti-MEM. () BIO-cGMP: 2 μM. () BIO-cGMP + OUA (10 μM). Control fluorescence values represent background. All other results are reported as BIO-cGMP fluorescence intensity above background. Data represent mean ± 1 SE. Scale bars represent 10 μm. Statistical significance was determined by using the repeated measures analysis with an unstructured covariance matrix in SAS PROC MIXED program. The ANOVA with permutation P value was based on 2,000 permutations of group assignment to individual N vales and a repeated measures analysis with an unstructured covariance matrix.