Fig. 2. Localization of InsP₃R-3 in polarized MDCK cells using two different specific antibodies: confocal analysis. MDCK plated at 10⁴ cells/cm² were cultured for 13 days and double stained using a monoclonal antibody (A) and a polyclonal antibody (B) specific for InsP₃R-3. The images shown correspond to a complete compiled z series of 30 xy sections taken in 0.2 µm steps. Note the patchy staining along the plasma membrane with, in some cases, a double row of patches (arrow). Bar, 10 µm.