Constitutive expression of GlyCAM-1 core protein in the rat cochlea.

Glycosylation-dependent cell adhesion molecule-1 (GIyCAM-1) is a mucin-like glycoprotein previously identified on high endothelial venules (HEV) of lymph nodes and also in lactating mammary glands. A specifically glycosilated form ofGIyCAM-1 on HEV has been shown to be a ligand for a leukocyte L-selectin, which plays an important role in leukocyte rolling along the inflamed endothelium. Here we report that GIyCAM-1 is also expressed in the cochlea. Immunohistochemistry revealed the lateral wall of the cochlea, tectorial membrane, modiolus, organ of Corti, and spiral modiolar vein (SMV) to be strongly stained with polyclonal anti-GIyCAM-1 antibody. Moreover, RT-PCR of the cochlear tissue by the use of specific oligonucleotide primers for rat GIyCAM-1 generated a 378 bp product which was then verified by nucleotide sequencing to represent GIyCAM-1. Electron microscopic investigation revealed the presence of GIyCAM-1 over the entire lumenal surface of the vessels, and the basolateral infoldings in stria vasc...