Whole nerve chorda tympani responses to sweeteners in C57BL/6ByJ and 129P3/J mice

The C57BL/6ByJ (B6) strain of mice exhibits higher preferences than does th e 129P3/J (129) strain for a variety of sweet tasting compounds. We measure d gustatory afferent responses of the whole chorda tympani nerve in these t wo strains using a broad array of sweeteners and other taste stimuli. Neura l responses were greater in B6 than in 129 mice to the sugars sucrose and m altose, the Polyol D-sorbitol and the non-caloric sweeteners Na saccharin, acesulfame-K, SC-45647 and sucralose. Lower neural response thresholds were also observed in the B6 strain for most of these stimuli, The strains did not differ in their neural responses to amino acids that are thought to tas te sweet to mice, with the exception Of L-proline, which evoked larger resp onses in the B6 strain. Aspartame and thaumatin, which taste sweet to human s but are not strongly preferred by B6 or 129 mice, did not evoke neural re sponses that exceeded threshold in either strain. The strains generally did not differ in their neural responses to NaCl, quinine and HCl. Thus, varia tion between the B6 and 129 strains in the peripheral gustatory system may contribute to differences in their consumption of many sweeteners.