Selective and reversible reduction of odor sensitivity in the rat by concanavalin A.

Rats were trained using an olfactometer to detect low concentrations of ethyl acetate (EA) or dimethyl disulphide vapor (DMDS). Concanavalin A (ConA) applied to the olfactory mucosa had no effect on ability of rats to detect low concentrations of EA but produced a marked deficit in detection in DMDS. DMDS detection performance returned to control levels 3 days after the ConA treatment. These results provide the first behavioral evidence for odor-specific inhibition by chemical modification of the olfactory epithelium and support the notion that ConA selectively inactivates one or more types (subclasses) of olfactory receptor proteins.