Effects of Drugs, Sex, and Age on Preference to Sweet Taste in Rats

The preference of sweet taste in rats is a phenomenon that is influenced by many factors. Drugs, sex, and age are three important aspects to consider when determining the underlying mechanisms that influence increased intake in the presence of sweet taste. Research has shown that drugs acting on receptors and neurotransmitters of brain mechanisms relevant to hedonic and reinforcement effects can alter the preference for sweet taste. Particularly important are drugs that act on benzodiazepine, dopamine, and serotonin receptors. When drugs facilitate their effects, sweet intake is increased and conversely, antagonists to these drugs decrease intake. Sex-defining hormones also play a role in preference to sweet taste; females tend to have higher preference for sweet solutions. The female hormone, estrogen, is said to increase the threshold for responding to sweet solutions. Studies on age have found that increase to preference of a sweet solution increases with age, but innate tendencies to prefer sweet tastants are also present from birth. These findings together can determine under what circumstances preference for sweet tastes are the greatest. This information can be used to work towards a cure for food-related epidemics, such as obesity by modifying the underlying systems of this phenomenon.