BEADED NERVE-TERMINALS IN FELINE LARYNGEAL MUCOSA

To investigate the mechanism of airway defense reflex, beaded nerve te rminals were studied by immunohistochemical techniques, In the supragl ottic region the density of PGP 9.5-immunoreactive nerve fibers was th e highest at the base of the glottic surface in the epiglottis, and in the glottic region it was the highest in the arytenoid region. In the subglottic region the number of positive nerve fibers was less than t he number at the base of the glottic surface in the epiglottis, and wh en the laryngeal mucosa was processed with NaOH to dissolve the epithe lium, it was possible to observe beaded nerve terminals more clearly. These beaded nerve terminals were found just beneath, in the epithelia l basement membrane, Electron microscopic examination of beaded nerve terminals revealed a large quantity of secretory granules and mitochon dria, suggesting that their structure is similar to that of nerve term inals. Thus these beaded nerve terminals may function as mechanorecept ors.