Comparing taste preference for menthol stereoisomers in adolescent Sprague–Dawley rats.
Psychology and Neuroscience
Objective: Menthol is an organic compound derived from the plant genus Mentha and is the most commonly added tastant to tobacco products. Users of mentholated tobacco products typically have greater dependence as well as poorer cessation outcomes. These effects are thought to be partially driven by menthol’s pleasing taste as well as menthol’s masking of aversive tastants in tobacco products, thereby increasing their palatability. However, there are two predominant stereoisomers contained in mentholated products in varying proportions: (−)-menthol and (+)-menthol. The palatability of these stereoisomers has not been directly tested. The objective of this study was to measure whether there are differences in oral taste preference among (−)-menthol and (+)-menthol. Method: Using a two-bottle choice assay, we measured taste preference over a range of (−)-menthol and (+)-menthol doses (10 mg/L, 50 mg/L, and 100 mg/L) in Sprague–Dawley adolescent (postnatal day 33–41) male and female rats. Results: Results showed a dose-dependent aversion to menthol at 50 mg/L and 100 mg/L (p < .0001), but not at 10 mg/L. These effects were not dependent on stereoisomer or sex. Conclusion: These findings suggest that (−)-menthol and (+)-menthol are equally potent in producing oral taste aversion. (PsycInfo Database Record (c) 2021 APA, all rights reserved) Public Significance Statement—Menthol is a commonly added tastant that masks bitter, unpleasant flavors in tobacco products which can increase drug dependence. This work shows that different stereoisomers of menthol, (−)-menthol and (+)-menthol, produce similar behavioral oral taste aversion responses in rats. This work suggests that both stereoisomers may play a role in masking unpleasant flavors, and therefore either may exacerbate tobacco dependence. (PsycInfo Database Record (c) 2021 APA, all rights reserved)
Lehr, Makenzie; Mitchell, Lauryn; Kline, Kaylee; Kerr, Lauren; and Wickham, Robert J., "Comparing taste preference for menthol stereoisomers in adolescent Sprague–Dawley rats." (2021). Faculty Publications. 822.