Prior exposure to nutritive and artificial sweeteners differentially alters the magnitude and persistence of sucrose-conditioned flavor preferences in BALB/c and C57BL/6 inbred mouse strains

Abstract

Murine genetic variance affects sucrose's ability to condition flavor preferences (CFP) relative to saccharin. Whereas BALB/c mice display robust sucrose- and fructose-CFP, C57BL/6 mice only display sucrose-CFP. Prior exposure to sucrose or saccharin solutions alters subsequent food choice responsiveness. The present study examined whether pre-exposure for one month to 10% sucrose or 0.2% saccharin altered subsequent sucrose-CFP in male and female BALB/c and C57BL/6 mice. Two weeks later, food-restricted mice were exposed to 10 CFP training trials with uniquely flavored 16% sucrose and 0.2% saccharin solutions. Two-bottle choice tests of the flavors mixed in saccharin followed for 4 weeks. Male mice weighed more than females across all conditions, and male BALB/c, but not C57BL mice consumed more 85 sucrose than females. No other notable sex differences were observed. BALB/c mice consumed more sucrose during pre-exposure and one-bottle training than C57BL/6 mice. Although the magnitudes of sucrose-CFP were comparable in two-bottle choice tests in water-exposed BALB/c and C57BL/6 mice, sucrose- and saccharin-exposed BALB/c mice displayed significantly greater sucrose-CFP preferences relative to C57BL/6 counterparts. These data indicate murine genetic variance in the effects of prior exposure to nutritive or non-nutritive sweeteners upon the magnitude of adult sugar-CFP.