Fig. 2. Actin and IP₃Rs are contained within the same region of the apical subplasamlemmal compartment of pancreatic acini. Isolated pancreatic cell clusters were fixed and stained with (A) antibodies to actin (mAb, green) and IP₃R2 (pAb, red), or (B) antibodies to actin (pAb, green) and IP₃R3 (mAb, red). Images are of confocal sections taken through the middle of the cell clusters. Arrows denote the apical membrane and arrowheads denote the basolateral membrane. Lower panels represent enlarged images of the regions covered by squares. Bar, 10 µm for image of cell cluster and 2 µm for enlarged image.