LAUSR

&NA; The medial prefrontal cortex (mPFC) has reciprocal projections with many cerebral structures that are crucial in the control of food ingestion behavior and reward processing; Thus the mPFC has an important function in taste memory recognition. Previous results indicate that long‐term consumption of sugar produces changes in appetitive re‐learning and suggest that this could trigger an escalating consumption due to the inability to learn new negative consequences related to the same taste. Further evidence suggests that general identity reward value could be encoded in the mPFC. Therefore, the purpose of this study was to evaluate in rats whether after 21 days of sugar consumption the increase in sweet taste preference and latent inhibition of conditioned taste aversion (CTA) were affected differentially by pharmacological activation or blockage of dopaminergic and &bgr;‐adrenergic receptors, in the mPFC, during CTA acquisition. Results showed that after long‐term sugar exposure, mPFC activation of &bgr;‐adrenergic receptors with clenbuterol delayed aversive memory extinction, but the blockade with propranolol or activation of dopaminergic receptors with apomorphine increased CTA latent inhibition and accelerated aversive memory extinction only after acute sugar exposure. Only dopaminergic blockade with haloperidol prevented sweet taste preference expression after long‐term sugar consumption, increased CTA latent inhibition and accelerated extinction after acute sugar exposure. Taken together, the present data provide evidence that catecholaminergic receptors in the mPFC after prolonged sugar consumption underwent functional changes related to re‐learning and new aversive taste learning. HighlightsLong‐term sugar consumption induces functional changes of catecholaminergic receptors.&bgr; ‐adrenergic receptors activation prevents memory extinction only after long‐term sugar consumption.&bgr;‐adrenergic receptors blockade increases latent inhibition only after short sugar exposure.Dopaminergic receptors blockade disrupts preference expression only after long‐term sugar consumption.