The adenoviral construct was injected in the portal vein as described under “Experimental Procedures,” and after 48 h the liver was excised, sectioned, stained with isoform-specific InsP3R antibodies (green), counterstained with the actin stain rhodamine phalloidin (red) to outline individual hepatocytes, and examined by confocal microscopy. A–C, distribution of type II InsP3R in control (noninfected) rat liver. The type II InsP3R is concentrated in the canalicular region of hepatocytes under normal conditions, as has been described previously (8). Scale bar, 20 µm. D–F, labeling for the type II InsP3R is nearly absent from hepatocytes 48 h after portal injection of adenoviral antisense. G–I, distribution of type I InsP3R in hepatocytes 48 h after injection of the adenoviral construct. The type I InsP3R is distributed throughout the cytosol of hepatocytes, similar to what is observed under normal conditions (Fig. 6, A–C). Therefore, the distribution of the type I isoform is not affected by the adenoviral antisense construct for the type II InsP3R.