The auditory context-dependent attenuation of taste neophobia depends on D1 dopamine receptor activity in mice.

Abstract

aste recognition memory in rodents is evident as taste neophobia disappears upon repeated taste exposures without aversive consequences, thus increasing the consumption of familiar edibles. The attenuation of taste neophobia (AN) induced by taste familiarity is auditory context-dependent in mice since neophobia to a familiar taste reappears with a novel auditory background. This effect depends on the integrity of the dorsal hippocampus but the potential role of dopamine has remained unexplored. In order to explore the involvement of dopamine through D1 dopamine receptors in AN, C57BL/6 mice were exposed to a 3% vinegar taste solution for 10 min throughout several consecutive days. An experimentally-controlled auditory background was used to define a context, which could either change or remain constant throughout all the drinking sessions. Systemic administration of the D1 dopamine receptor antagonist SCH-23390 induced a similar effect to that of an auditory context change while it was kept constant and systemic administration of SKF-81297 prevented the contextual modulation of AN when the auditory context changed. Additionally, SCH-23390 injection on the following day to the auditory context change further impaired AN, thus suggesting the relevance of dopamine in the consolidation of the context dependency of taste recognition memory. We conclude that the context dependency of the AN involves dopaminergic activity mediated by D1 receptors which might be responsible for proper acquisition of safe taste recognition memory.