LAUSR

ABSTRACT Environmental rewards and Pavlovian reward cues can acquire incentive salience, thereby eliciting incentive motivational states and instigate reward‐seeking. In rats, the incentive salience of food cues can be measured during a Pavlovian conditioned approach paradigm, in which rats engage in cue‐directed approach (“sign‐tracking”) or approach the food delivery location (“goal‐tracking”). While it has been shown that dopamine signaling is necessary for sign‐tracking, some studies have suggested that norepinephrine is involved in learning to sign‐track as well. Thus, in order to investigate the influence of norepinephrine in Pavlovian conditioned approach, we administered three adrenergic drugs while rats learned that a food cue (an illuminated, retractable lever) preceded the delivery of banana‐flavored food pellets into a food‐cup. We found that pre‐session injections of disulfiram (a dopamine‐&bgr;‐hydroxylase inhibitor) inhibited the development of sign‐tracking, but goal‐tracking was only affected at the high dose. In one experiment, post‐session injections of disulfiram blocked the development of sign‐tracking, although this effect was not replicated in a separate set of rats. Post‐session injections of prazosin (an &agr;1‐adrenergic receptor antagonist) and propranolol (a &bgr;‐adrenergic receptor antagonist) also blocked the development of sign‐tracking but not goal‐tracking. Taken together, these results suggest that adrenergic transmission mediates the acquisition of sign‐tracking but not goal‐tracking, and thus plays a selective role in the attribution of incentive salience food cues.