Intercellular junctions in the rat vomeronasal neuroepithelium: a freeze-fracture study

The intercellular junctions (tight junctions, desmosomes and gasp junctions) of the vomeronasal neuroepithelium of male Wistar rats were investigated by freeze-fracture. Tight junctions were localized apically sealing the intercellular clefts. Tight junctions were composed of 6 to 12 junctional strands arranged in a meshwork. the distance between the most apical and the most basal junctional strand was 430 +/- 90 nm. No proper distinction could be made between receptor-supporting and supporting-supporting cell tight junctions. Besides tight junctions, numerous desmosomes and ga junctions were found. Desmosomes were present on the supporting and receptor cell membranes below the level of the tight junctions. Gap junctions could be seen at the level of the perikarya of the supporting and receptor cells. They were only found on supporting cell membranes.