MUCOCILIARY TRANSPORT IN LIVING TISSUE - THE 2-LAYER MODEL CONFIRMED IN THE MUSSEL MYTILUS-EDULIS L

The present study combined video confocal laser-microscopy (1) and tis sue reflectance and autofluorescence to visualize mucus position and m ucociliary transport in excised living gill tissue from the blue musse l Mytilus edulis. Rafts of mucus and embedded particles were transport ed atop a periciliary space traversed by frontal cilia, which engaged the mucus layer and moved it during the effective stroke, disengaging and completing the cycle during the recovery stroke. These results con firm the two-layer model for mucociliary transport in the mussel gill. Given the conservative nature of ciliated epithelial structure and fu nction (2, 3), and the structural similarity of mucociliary surfaces a s diverse as terrestrial vertebrate respiratory epithelium and mollusc an gill, the two-latter mechanism of mucociliary transport may be a ge neral feature of Metazoan biology.