ABSTRACT
Developing mammals are highly dependent on the sense of taste to find and choose sources of food. From the earliest postnatal ages, the gustatory system plays a major role in ingestive behaviors and the proper utilization of food in conjunction with homeostatic systems. In addition to discrimination of taste quality and quantity, this sensory system must complement the needs of changing nutritive demands and agerelated changes in gastrointestinal function by processing sensory information in a developmentally appropriate way. For example, age-related changes in electrolyte levels determined by gut and renal development1 may influence age-related changes in gustatory function. Although this hypothesis has not been tested directly, changes in electrolytes, such as plasma sodium levels, occur temporally with increased peripheral taste responses during the first three postnatal weeks in rats.2-5 Conversely, visceral function is impacted through reflexes triggered by the gustatory system. For example, preabsorptive pancreatic release of insulin in adult animals is triggered by the taste of sugar.6 Therefore, developmental plasticity in gustatory function, especially plasticity resident to the CNS, may have wide ranging physiological effects beyond sensory coding.
