Fig. 9. (A) An immunoelectron micrograph showing the small granular gland immunolabeled for AQP-x5. Labels are visible in the apical plasma membrane of the secretory cells (sc) in the small granular gland. (B) An immunoelectron micrograph showing secretory and mitochondria-rich cells labeled with the antibody preabsorbed with the antigen. Immunogold particles were seen at background levels, especially in mitochondria-rich cell (arrowheads). l, lumen; mrc, mitochondria-rich cell; m, mitochondria; asterisks, secretory granule. Scale bar, 1 µm.