Abstract: | Prostaglandins (PG) E1 and E2 were applied topically to the receptive fields of feline laryngeal and pharyngeal sensory receptors, while action potentials were recorded from single - or few-fiber preparations of the superior laryngeal nerve. When initially dissolved in ethanol, PGs stimulated these sensory receptors. If ethanol was not used as a solvent for the PGs they did not stimulate the sensory receptors. Similarly, local application of dilute (0.025%, v/v) solutions of ethanol alone excited the receptors, whereas phosphate buffer alone did not. Thus PGE1 and PGE2 do not themselves stimulate sensory receptors in the larynx and pharynx. These findings suggest that irritant properties of PGEs on upper airways are attributable to the ethanol used as a solvent. |