MICROSPHERE ABSORPTION BY THE NASAL-MUCOSA OF THE RAT

Uptake by nasal epithelial tissue of fluorescent polystyrene latex mic roparticles of diameter 0.8 mum was studied in rats after single intra nasal dosing. At intervals following administration, particles were ob served in the blood compartment. Peak concentration of particles occur red in normal animals at 10 min. At 24 h some particles were still pre sent in these animals' circulation. Throughout the sampling, tracheoto mised animals demonstrated a steady state presence of particles. These results show that the uptake and translocation of solid particles doe s also take place through the nasal epithelial lining as it does throu gh gut epithelia, possibly through the nasal associated lymphatic tiss ue.