Sex differences in polysaccharide and sugar preferences in rats

Abstract

The preferences of adult male and female rats for sucrose and polysaccharide (Polycose) solutions were measured in three experiments. In Experiment 1, male and female rats did not differ in their preference for molar solutions of sucrose or Polycose as measured by 24-hr solution vs. water tests. In Experiment 2, however, male rats displayed a greater preference for Polycose, and females a greater preference for sucrose as measured in 3-min and 30-min/day sucrose vs. Polycose tests. Both sexes preferred Polycose to sucrose at low concentrations, but switched their preference at higher concentrations. Experiment 3 revealed that both male and female rats strongly preferred 32% sucrose to 32% Polycose in 30-min/day two-solution tests, but this preference did not persist when the rats were given 24-hr/day access to the two solutions. Male rats lost their sucrose preference, while female rats developed a preference for Polycose over sucrose. The sexes also differed in that the female rats increased their total caloric intake more and consumed proportionately more carbohydrate than did the male rats during the 24-hr/day test. The findings demonstrate that while both male and female rats have an avid appetite for polysaccharide and sucrose solutions, they differ in their short-term and long-term relative preferences for the two carbohydrates, as well as in their caloric and diet selection responses to the carbohydrate solutions. The possible functional significance of these sex differences are discussed.